{"product_id":"sea-to-summit-alpine-down-sleeping-bag","title":"Sea to Summit Alpine Down Sleeping Bag","description":"\u003cmeta charset=\"UTF-8\"\u003e\u003cmeta name=\"viewport\" content=\"width=device-width, initial-scale=1.0\"\u003e\u003ctitle\u003eAlpine Down Sleeping Bag\u003c\/title\u003e\u003cstyle\u003e\n@import url('https:\/\/fonts.googleapis.com\/css2?family=Barlow+Condensed:wght@400;600;700;800\u0026family=Barlow:wght@300;400;500;600\u0026display=swap');\n:root { --black: #0a0a0a; --white: #ffffff; --mid: #f5f5f5; --border: #e8e8e8; --muted: #999; --body: #222; }\n* { box-sizing: border-box; margin: 0; padding: 0; }\n.spur-wrap { font-family: 'Barlow', sans-serif; background: var(--white); color: var(--black); max-width: 1100px; margin: 0 auto; padding: 48px 24px; }\n.spur-header { display: flex; align-items: flex-end; justify-content: space-between; margin-bottom: 48px; border-bottom: 1px solid var(--border); padding-bottom: 24px; flex-wrap: wrap; gap: 12px; }\n.spur-title { font-family: 'Barlow Condensed', sans-serif; font-size: clamp(28px, 5vw, 48px); font-weight: 800; letter-spacing: -0.02em; line-height: 1; text-transform: uppercase; }\n.spur-meta { font-size: 12px; font-weight: 500; letter-spacing: 0.12em; text-transform: uppercase; color: var(--muted); }\n.tab-radio { display: none; }\n.tab-nav { display: flex; gap: 4px; margin-bottom: 32px; flex-wrap: wrap; }\n.tab-nav label { font-family: 'Barlow Condensed', sans-serif; font-size: 14px; font-weight: 700; letter-spacing: 0.1em; text-transform: uppercase; padding: 10px 24px; background: var(--mid); color: var(--muted); border: 1px solid var(--border); cursor: pointer; transition: all 0.15s; border-radius: 2px; display: inline-block; user-select: none; }\n.tab-nav label:hover { color: var(--black); border-color: #aaa; }\n.spur-panels .tab-panel { display: none; }\n#tab-desc:checked ~ .tab-nav label[for=\"tab-desc\"],\n#tab-key:checked ~ .tab-nav label[for=\"tab-key\"],\n#tab-specs:checked ~ .tab-nav label[for=\"tab-specs\"],\n#tab-care:checked ~ .tab-nav label[for=\"tab-care\"] { background: var(--black); color: var(--white); border-color: var(--black); }\n#tab-desc:checked ~ .spur-panels .desc-panel { display: block; }\n#tab-key:checked ~ .spur-panels .key-panel { display: block; }\n#tab-specs:checked ~ .spur-panels .specs-panel { display: block; }\n#tab-care:checked ~ .spur-panels .care-panel { display: block; }\n.spur-panel p { font-size: 14px; font-weight: 300; line-height: 1.7; color: var(--body); margin-bottom: 16px; }\n.desc-intro { font-size: 16px; font-weight: 400; line-height: 1.65; color: var(--body); margin-bottom: 28px; padding-bottom: 24px; border-bottom: 1px solid var(--border); }\n.key-section { border-bottom: 1px solid var(--border); padding: 16px 0; }\n.key-section:last-child { border-bottom: none; }\n.key-title { font-family: 'Barlow Condensed', sans-serif; font-size: 13px; font-weight: 700; letter-spacing: 0.1em; text-transform: uppercase; margin-bottom: 6px; }\n.key-desc { font-size: 14px; font-weight: 300; color: var(--body); line-height: 1.5; }\n.spec-row { display: grid; grid-template-columns: 200px 1fr; border-bottom: 1px solid var(--border); }\n.spec-key { font-size: 12px; font-weight: 500; letter-spacing: 0.05em; text-transform: uppercase; color: var(--muted); padding: 12px 16px 12px 0; }\n.spec-val { font-size: 14px; font-weight: 300; color: var(--body); padding: 12px 0; line-height: 1.5; }\n.spec-category { font-family: 'Barlow Condensed', sans-serif; font-size: 13px; font-weight: 700; letter-spacing: 0.1em; text-transform: uppercase; margin: 24px 0 8px 0; color: var(--muted); }\n.spec-category:first-child { margin-top: 0; }\n.spec-table { width: 100%; border-collapse: collapse; margin: 12px 0; }\n.spec-table th, .spec-table td { padding: 10px 14px; text-align: left; border: 1px solid var(--border); font-size: 13px; font-weight: 300; }\n.spec-table th { font-family: 'Barlow Condensed', sans-serif; font-weight: 700; letter-spacing: 0.08em; text-transform: uppercase; background: var(--mid); font-size: 12px; color: var(--muted); }\n.benefits-row { display: grid; grid-template-columns: repeat(auto-fit, minmax(160px, 1fr)); gap: 16px; margin-top: 8px; }\n.benefit-card { border: 1px solid var(--border); border-radius: 4px; padding: 16px 14px; text-align: center; }\n.benefit-name { font-family: 'Barlow Condensed', sans-serif; font-size: 13px; font-weight: 700; letter-spacing: 0.1em; text-transform: uppercase; margin-bottom: 6px; }\n.benefit-desc { font-size: 12px; font-weight: 300; color: #555; line-height: 1.45; }\n.tech-badges { display: flex; flex-wrap: wrap; gap: 12px; margin: 16px 0 24px 0; }\n.tech-badge { border: 1px solid var(--border); border-radius: 20px; padding: 8px 16px; font-size: 11px; font-weight: 600; letter-spacing: 0.1em; text-transform: uppercase; color: var(--black); background: var(--mid); }\n@media (max-width: 600px) { .spec-row { grid-template-columns: 1fr; } .spec-key { padding-bottom: 2px; } .spec-val { padding-top: 0; padding-bottom: 12px; } .spec-table { font-size: 11px; } .spec-table th, .spec-table td { padding: 8px 10px; } }\n\u003c\/style\u003e\u003cscript src=\"chrome-extension:\/\/idnnbdplmphpflfnlkomgpfbpcgelopg\/inpage.js\" id=\"xverse-wallet-provider\" data-is-priority=\"true\"\u003e\u003c\/script\u003e\u003cdiv class=\"spur-wrap\"\u003e\n\u003cdiv class=\"spur-header\"\u003e\n\u003cdiv class=\"spur-title\"\u003eAlpine Down Sleeping Bag\u003c\/div\u003e\n\u003cdiv class=\"spur-meta\"\u003eSleep System · Extreme Cold · Mountaineering\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cinput type=\"radio\" name=\"spur-tabs\" id=\"tab-desc\" class=\"tab-radio\" checked\u003e\u003cinput type=\"radio\" name=\"spur-tabs\" id=\"tab-key\" class=\"tab-radio\"\u003e\u003cinput type=\"radio\" name=\"spur-tabs\" id=\"tab-specs\" class=\"tab-radio\"\u003e\u003cinput type=\"radio\" name=\"spur-tabs\" id=\"tab-care\" class=\"tab-radio\"\u003e\u003cdiv class=\"tab-nav\"\u003e\n\u003clabel for=\"tab-desc\"\u003eDescription\u003c\/label\u003e\u003clabel for=\"tab-key\"\u003eKey Features\u003c\/label\u003e\u003clabel for=\"tab-specs\"\u003eSpecifications\u003c\/label\u003e\u003clabel for=\"tab-care\"\u003eCare\u003c\/label\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"spur-panels\"\u003e\n\u003c!-- DESCRIPTION PANEL --\u003e\u003cdiv class=\"tab-panel desc-panel\"\u003e\u003cp class=\"desc-intro\"\u003eGear up for your next high altitude or colder latitude adventure with the Alpine Down Sleeping Bag. The expedition mummy fit provides ample space for winter gear, while the modified Free-Flow Zip system provides ventilation and versatility. Complex construction throughout and 850+ fillpower, RDS-certified non-PFAS Ultra-Dry Goose Down delivers maximum warmth retention for serious cold-weather pursuits.\u003c\/p\u003e\u003c\/div\u003e\n\u003c!-- KEY FEATURES PANEL --\u003e\u003cdiv class=\"tab-panel key-panel\"\u003e\n\u003cdiv class=\"key-section\"\u003e\n\u003cdiv class=\"key-title\"\u003e-20°F Rating\u003c\/div\u003e\n\u003cdiv class=\"key-desc\"\u003eISO Lower Limit of -20°F \/ -29°C — rated for high-altitude mountaineering and extreme cold-weather use.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"key-section\"\u003e\n\u003cdiv class=\"key-title\"\u003e850+ Fill Down\u003c\/div\u003e\n\u003cdiv class=\"key-desc\"\u003ePremium 850+ fillpower goose down — top-tier loft and warmth-to-weight ratio. Maximum thermal performance.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"key-section\"\u003e\n\u003cdiv class=\"key-title\"\u003eWater-Resistant Down\u003c\/div\u003e\n\u003cdiv class=\"key-desc\"\u003eUltra-Dry Down treatment (non-PFAS) protects down from moisture — maintains loft in damp conditions.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"key-section\"\u003e\n\u003cdiv class=\"key-title\"\u003eFree-Flow Zip System\u003c\/div\u003e\n\u003cdiv class=\"key-desc\"\u003eFull-length + half-length zipper on opposite side for excellent temperature regulation and ventilation.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"key-section\"\u003e\n\u003cdiv class=\"key-title\"\u003eExpedition Mummy Fit\u003c\/div\u003e\n\u003cdiv class=\"key-desc\"\u003eRoomy mummy cut provides space for performance clothing and gear that shouldn't freeze.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"key-section\"\u003e\n\u003cdiv class=\"key-title\"\u003eSustainable Sourcing\u003c\/div\u003e\n\u003cdiv class=\"key-desc\"\u003eRDS-certified down (Responsible Down Standard) — ethically sourced, traceable supply chain.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"key-section\"\u003e\n\u003cdiv class=\"key-title\"\u003e850+ Fillpower RDS Goose Down (NEW — PREMIUM INSULATION)\u003c\/div\u003e\n\u003cdiv class=\"key-desc\"\u003ePremium \u003cstrong\u003e850+ fillpower goose down\u003c\/strong\u003e — top-tier loft and warmth-to-weight ratio. Fillpower measures the volume one ounce of down fills (in cubic inches); higher fillpower = more loft = more warmth for the same weight. 850+ is in the ultra-premium range (800+ is premium, 850+ is ultra-premium). Combined with \u003cstrong\u003eRDS (Responsible Down Standard)\u003c\/strong\u003e certification, ensuring ethical sourcing and full traceability from farm to factory.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"key-section\"\u003e\n\u003cdiv class=\"key-title\"\u003eUltra-Dry Down Treatment (NEW — WATER-RESISTANT DOWN)\u003c\/div\u003e\n\u003cdiv class=\"key-desc\"\u003eThe down is treated with \u003cstrong\u003eUltra-Dry Down\u003c\/strong\u003e — a non-PFAS water-resistant treatment that protects individual down clusters from moisture. Wet down loses loft and warmth (and takes a long time to dry); Ultra-Dry-treated down maintains loft in damp conditions and dries faster. Critical for alpine and mountaineering use where condensation, snow, and humidity are constant threats. Non-PFAS formulation avoids the persistent \"forever chemicals\" found in older DWR treatments.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"key-section\"\u003e\n\u003cdiv class=\"key-title\"\u003eRecycled 20D Nylon Shell with Non-PFAS DWR\u003c\/div\u003e\n\u003cdiv class=\"key-desc\"\u003eThe shell is \u003cstrong\u003erecycled 20D nylon\u003c\/strong\u003e with a \u003cstrong\u003enon-PFAS DWR (Durable Water Repellent)\u003c\/strong\u003e finish — light and durable, with water resistance for damp conditions. 20D is a balance of weight and durability; not the lightest (10D\/15D), not the heaviest (40D\/70D). The DWR finish beads light moisture without using PFAS chemicals.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"key-section\"\u003e\n\u003cdiv class=\"key-title\"\u003eWater-Resistant Hood \u0026amp; Footbox\u003c\/div\u003e\n\u003cdiv class=\"key-desc\"\u003eThe hood and footbox use a \u003cstrong\u003ehighly water-resistant, breathable fabric\u003c\/strong\u003e — extra moisture protection in areas most likely to contact snow, condensation, or frost. Ideal for bivy sacks or snow cave camping where the bag may contact frozen surfaces directly.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"key-section\"\u003e\n\u003cdiv class=\"key-title\"\u003eFree-Flow Zip System (NEW — VENTILATION TECH)\u003c\/div\u003e\n\u003cdiv class=\"key-desc\"\u003eThe Free-Flow Zip System combines a \u003cstrong\u003efull-length zipper\u003c\/strong\u003e with a \u003cstrong\u003ehalf-length zipper on the opposite side\u003c\/strong\u003e — gives you multiple ventilation options:\n- Full zipper open = blanket mode (warm nights)\n- Both zippers open = flat quilt (very warm nights, or want to use over a sleeping pad)\n- Top only = standard mummy configuration\n- Half-side only = foot ventilation (cold feet but warm body, or vice versa)\n- Both closed = full mummy (cold nights)\n\nThe two-zipper system is significantly more versatile than single-zip sleeping bags.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"key-section\"\u003e\n\u003cdiv class=\"key-title\"\u003eHighly Breathable Liner\u003c\/div\u003e\n\u003cdiv class=\"key-desc\"\u003eThe interior liner is engineered for \u003cstrong\u003ehigh breathability\u003c\/strong\u003e — moves moisture vapor away from your body to prevent the clammy feeling that builds up in less-breathable bags. Critical for multi-day expeditions where you can't fully dry out the bag between nights.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"key-section\"\u003e\n\u003cdiv class=\"key-title\"\u003eTechnical Hood \u0026amp; Footbox\u003c\/div\u003e\n\u003cdiv class=\"key-desc\"\u003eBoth the hood and footbox are technically shaped for warmth retention. The hood cinches tight around the head (only face exposed). The footbox has extra space for boot-wearing feet but is shaped to minimize dead air space. Generous \u003cstrong\u003edraft tubes\u003c\/strong\u003e along both zippers prevent cold air infiltration through the zipper teeth.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"key-section\"\u003e\n\u003cdiv class=\"key-title\"\u003eQuiltLock System (NEW — TECH FEATURE)\u003c\/div\u003e\n\u003cdiv class=\"key-desc\"\u003e\n\u003cstrong\u003eQuiltLock\u003c\/strong\u003e is STS's proprietary system for securing the sleeping bag to a quilt or sleeping pad — keeps the bag in place during restless sleep and allows the bag to function as a quilt when fully unzipped. Specific QuiltLock functionality depends on the paired STS quilt\/pad model.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"key-section\"\u003e\n\u003cdiv class=\"key-title\"\u003eTemperature Rating (IMPORTANT)\u003c\/div\u003e\n\u003cdiv class=\"key-desc\"\u003e\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"key-section\"\u003e\n\u003cdiv class=\"key-title\"\u003eISO Lower Limit Rating (-20°F \/ -29°C)\u003c\/div\u003e\n\u003cdiv class=\"key-desc\"\u003eThe Alpine Down is rated to \u003cstrong\u003eISO Lower Limit -20°F \/ -29°C\u003c\/strong\u003e — the formal temperature standard for sleeping bags. The ISO Lower Limit is the temperature at which an average man can sleep for 8 hours without feeling cold. \u003cstrong\u003eFor women\u003c\/strong\u003e, the equivalent comfort rating is -2°F \/ -19°C (per the spec sheet). The bag is engineered for serious cold-weather use: high-altitude mountaineering, winter camping, alpine ascents, polar travel.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"key-section\"\u003e\n\u003cdiv class=\"key-title\"\u003eRegular \/ Long\u003c\/div\u003e\n\u003cdiv class=\"key-desc\"\u003eTwo sizes — Regular fits users up to 72.05 in \/ 183 cm; Long fits users up to 77.95 in \/ 198 cm. Long version adds ~6.5 oz of weight and slightly more fill for taller users.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c!-- SPECIFICATIONS PANEL --\u003e\u003cdiv class=\"tab-panel specs-panel\"\u003e\n\u003cp class=\"spec-category\"\u003eTemperature Rating\u003c\/p\u003e\n\u003cdiv class=\"spec-row\"\u003e\n\u003cdiv class=\"spec-key\"\u003eISO Lower Limit (Men's)\u003c\/div\u003e\n\u003cdiv class=\"spec-val\"\u003e-20°F \/ -29°C\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"spec-row\"\u003e\n\u003cdiv class=\"spec-key\"\u003eISO Comfort (Women's)\u003c\/div\u003e\n\u003cdiv class=\"spec-val\"\u003e-2°F \/ -19°C\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"spec-row\"\u003e\n\u003cdiv class=\"spec-key\"\u003eClimate Category\u003c\/div\u003e\n\u003cdiv class=\"spec-val\"\u003eExtreme Cold \/ Mountaineering\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cp class=\"spec-category\"\u003eDimensions \u0026amp; Weight (by size)\u003c\/p\u003e\n\u003ctable class=\"spec-table\"\u003e\n\u003cthead\u003e\u003ctr\u003e\n\u003cth\u003eMeasurement\u003c\/th\u003e\n\u003cth\u003eRegular\u003c\/th\u003e\n\u003cth\u003eLong\u003c\/th\u003e\n\u003c\/tr\u003e\u003c\/thead\u003e\n\u003ctbody\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eTotal Weight\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e51.5 oz \/ 1460 g\u003c\/td\u003e\n\u003ctd\u003e58.0 oz \/ 1644 g\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eFill Weight\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e35.27 oz \/ 1000 g\u003c\/td\u003e\n\u003ctd\u003e40.04 oz \/ 1135 g\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eCompressed Volume\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e12.6 L\u003c\/td\u003e\n\u003ctd\u003e14 L\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eRecommended User Height\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e72.05 in \/ 183 cm\u003c\/td\u003e\n\u003ctd\u003e77.95 in \/ 198 cm\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp class=\"spec-category\"\u003eMaterials \u0026amp; Construction\u003c\/p\u003e\n\u003cdiv class=\"spec-row\"\u003e\n\u003cdiv class=\"spec-key\"\u003eShell\u003c\/div\u003e\n\u003cdiv class=\"spec-val\"\u003e100% Recycled Nylon (20D, non-PFAS DWR finish)\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"spec-row\"\u003e\n\u003cdiv class=\"spec-key\"\u003eLining\u003c\/div\u003e\n\u003cdiv class=\"spec-val\"\u003e100% Nylon (highly breathable)\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"spec-row\"\u003e\n\u003cdiv class=\"spec-key\"\u003eDown Fill\u003c\/div\u003e\n\u003cdiv class=\"spec-val\"\u003e90\/10 Goose Down (RDS-certified, 850+ fillpower, Ultra-Dry Down treatment, non-PFAS)\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"spec-row\"\u003e\n\u003cdiv class=\"spec-key\"\u003eStuff Sack\u003c\/div\u003e\n\u003cdiv class=\"spec-val\"\u003e100% Nylon (included, excluding trims)\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"spec-row\"\u003e\n\u003cdiv class=\"spec-key\"\u003eZippers\u003c\/div\u003e\n\u003cdiv class=\"spec-val\"\u003eFree-Flow Zip System (full-length + half-length on opposite side)\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"spec-row\"\u003e\n\u003cdiv class=\"spec-key\"\u003eHood\/Footbox Fabric\u003c\/div\u003e\n\u003cdiv class=\"spec-val\"\u003eHighly water-resistant, breathable\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"spec-row\"\u003e\n\u003cdiv class=\"spec-key\"\u003eDraft Tubes\u003c\/div\u003e\n\u003cdiv class=\"spec-val\"\u003eGenerous draft tubes on both zippers\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cp class=\"spec-category\"\u003ePerformance (STS scales)\u003c\/p\u003e\n\u003cdiv class=\"spec-row\"\u003e\n\u003cdiv class=\"spec-key\"\u003eWeight Class\u003c\/div\u003e\n\u003cdiv class=\"spec-val\"\u003eMidweight (heavier than ultralight summer bags — appropriate for -20°F rating)\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"spec-row\"\u003e\n\u003cdiv class=\"spec-key\"\u003eClimate\u003c\/div\u003e\n\u003cdiv class=\"spec-val\"\u003eExtreme Cold (most extreme category on STS scale)\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cp class=\"spec-category\"\u003eCompatibility\u003c\/p\u003e\n\u003cdiv class=\"spec-row\"\u003e\n\u003cdiv class=\"spec-key\"\u003eUse Cases\u003c\/div\u003e\n\u003cdiv class=\"spec-val\"\u003eHigh-altitude mountaineering, winter camping, alpine ascents, polar travel, snow cave camping, bivy trips, expedition climbing\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"spec-row\"\u003e\n\u003cdiv class=\"spec-key\"\u003eSleeping Pad Pairing\u003c\/div\u003e\n\u003cdiv class=\"spec-val\"\u003ePair with a high R-value insulated sleeping pad (R 5+) for full -20°F system warmth\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"spec-row\"\u003e\n\u003cdiv class=\"spec-key\"\u003eSleeping Bag Liner Pairing\u003c\/div\u003e\n\u003cdiv class=\"spec-val\"\u003eCompatible with STS Silk Blend, Reactor Fleeceweight, and other standard sleeping bag liners for added warmth\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cp class=\"spec-category\"\u003eProfile\u003c\/p\u003e\n\u003cdiv class=\"spec-row\"\u003e\n\u003cdiv class=\"spec-key\"\u003eBrand\u003c\/div\u003e\n\u003cdiv class=\"spec-val\"\u003eSea to Summit (Australian outdoor gear, founded 1994)\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"spec-row\"\u003e\n\u003cdiv class=\"spec-key\"\u003eCategory\u003c\/div\u003e\n\u003cdiv class=\"spec-val\"\u003eSleeping Bag \/ Down Sleeping Bag \/ Mountaineering Sleeping Bag\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"spec-row\"\u003e\n\u003cdiv class=\"spec-key\"\u003eActivity\u003c\/div\u003e\n\u003cdiv class=\"spec-val\"\u003eHigh-altitude mountaineering, winter camping, alpine ascents, polar travel, expedition climbing\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"spec-row\"\u003e\n\u003cdiv class=\"spec-key\"\u003eSeason\u003c\/div\u003e\n\u003cdiv class=\"spec-val\"\u003eWinter \/ Extreme cold (rated for -20°F \/ -29°C use)\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c!-- CARE PANEL --\u003e\u003cdiv class=\"tab-panel care-panel\"\u003e\n\u003cdiv class=\"key-section\"\u003e\n\u003cdiv class=\"key-title\"\u003eCleaning (NEW — DOWN BAG SPECIFIC)\u003c\/div\u003e\n\u003cdiv class=\"key-desc\"\u003eHand wash or machine wash (front-loading washer only, no top-loaders with agitators) in cold water with a \u003cstrong\u003edown-specific technical wash\u003c\/strong\u003e like Nikwax Down Wash or Grangers Down Wash. Regular detergent will strip the natural oils from down and degrade the Ultra-Dry Down treatment. Wash infrequently — most down bags only need washing once every 5-10 trips. Spot clean between washes with a damp cloth. \u003cstrong\u003eDo not dry clean\u003c\/strong\u003e — solvents strip the down treatment and damage the shell DWR.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"key-section\"\u003e\n\u003cdiv class=\"key-title\"\u003eDrying (NEW — DOWN BAG SPECIFIC)\u003c\/div\u003e\n\u003cdiv class=\"key-desc\"\u003e\n\u003cstrong\u003eTumble dry low\u003c\/strong\u003e with \u003cstrong\u003e3-4 clean tennis balls or dryer balls\u003c\/strong\u003e — the balls break up down clumps as the bag dries, restoring loft. Drying takes 2-4 hours minimum — don't rush. Ensure the bag is \u003cstrong\u003ecompletely dry\u003c\/strong\u003e before storage — any retained moisture will cause mildew and down clumping. Can also air dry in sunlight on a dry day, but fluff by hand periodically. Never store a damp down bag.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"key-section\"\u003e\n\u003cdiv class=\"key-title\"\u003eStorage (NEW — DOWN BAG SPECIFIC)\u003c\/div\u003e\n\u003cdiv class=\"key-desc\"\u003e\n\u003cstrong\u003eStore UNCOMPRESSED in a large cotton storage sack\u003c\/strong\u003e — not the included compression stuff sack. Long-term compression damages down loft permanently. The included stuff sack is for transport only. STS typically includes a large cotton storage sack with their down bags. Store in a cool, dry place away from direct sunlight (UV degrades the shell fabric and the down).\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"key-section\"\u003e\n\u003cdiv class=\"key-title\"\u003eUltra-Dry Down Treatment Care\u003c\/div\u003e\n\u003cdiv class=\"key-desc\"\u003eThe Ultra-Dry Down treatment is durable but will wear off with years of use and washing. To refresh: use Nikwax Down Proof or similar down-specific water-resistant treatments after washing. Apply to clean, dry bag and tumble dry low with tennis balls to activate the treatment.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"key-section\"\u003e\n\u003cdiv class=\"key-title\"\u003eShell DWR Refresh\u003c\/div\u003e\n\u003cdiv class=\"key-desc\"\u003eThe shell's non-PFAS DWR will wear off with use. Refresh with a PFC-free spray-on DWR (Nikwax TX.Direct Spray-On, Grangers Performance Repel, Gear Aid ReviveX). Apply to clean bag, let cure for 24 hours before use.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"key-section\"\u003e\n\u003cdiv class=\"key-title\"\u003eZipper Care\u003c\/div\u003e\n\u003cdiv class=\"key-desc\"\u003eBoth zippers (full-length and half-length) should be kept clean and lubricated. After exposure to sand, salt, or dirt, rinse with fresh water. If zippers stick, apply a small amount of beeswax or a graphite pencil tip to the teeth — avoid silicone-based lubricants which attract dirt.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"key-section\"\u003e\n\u003cdiv class=\"key-title\"\u003eDraft Tube Maintenance\u003c\/div\u003e\n\u003cdiv class=\"key-desc\"\u003eThe draft tubes (insulated tubes along zippers) prevent cold air infiltration. If a draft tube shifts or develops gaps, you can hand-position it back into place. Don't aggressively stuff the draft tube back inside the bag shell — it can damage the stitching.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"key-section\"\u003e\n\u003cdiv class=\"key-title\"\u003eHood \u0026amp; Footbox Care\u003c\/div\u003e\n\u003cdiv class=\"key-desc\"\u003eThe hood cinches tight around the head — inspect the drawcord and toggle periodically for wear. The footbox is shaped for boot-wearing feet; if the stitching fails, contact STS warranty service.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"key-section\"\u003e\n\u003cdiv class=\"key-title\"\u003eLong-Term Loft Maintenance\u003c\/div\u003e\n\u003cdiv class=\"key-desc\"\u003eDown bags lose some loft over years of use as the down clusters break down. To refresh loft: tumble dry low with tennis balls for 30 minutes every 6-12 months. The mechanical action separates down clusters and restores some loft. Replace bags showing significant loft loss (typically 10+ years of regular use).\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"key-section\"\u003e\n\u003cdiv class=\"key-title\"\u003eRepair\u003c\/div\u003e\n\u003cdiv class=\"key-desc\"\u003eSmall shell tears: STS repair patches or any silicone\/PU repair tape. Large tears, baffle failures, or zipper failures: contact STS warranty service. Down bags are significant investments; STS offers repair services for out-of-warranty bags.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003cdiv class=\"key-section\"\u003e\n\u003cdiv class=\"key-title\"\u003eExpedition Tip\u003c\/div\u003e\n\u003cdiv class=\"key-desc\"\u003eFor multi-day mountaineering expeditions, pair the Alpine Down with a high R-value sleeping pad (R 5+) — the sleeping pad insulation is just as important as the bag for cold-weather warmth. Sleep in dry base layers (not the clothes you hiked in — sweat will cool your body overnight). Stuff a water bottle with hot water and place it in the footbox for a \"hot water bottle\" warming effect. The Free-Flow Zip System lets you vent your feet if you overheat, or vent your body if you need to cool down.\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\n\u003c\/div\u003e\u003cdiv id=\"torrent-scanner-popup\" style=\"display: none;\"\u003e\u003c\/div\u003e","brand":"Sea to Summit","offers":[{"title":"Blazing Yellow \/ -29C|-20F Regular","offer_id":52743296418112,"sku":"S2042","price":934.0,"currency_code":"USD","in_stock":false},{"title":"Blazing Yellow \/ -29C|-20F Long","offer_id":52743296450880,"sku":"S2043","price":984.0,"currency_code":"USD","in_stock":false}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0446\/7487\/5549\/files\/S2042_1f8a080b-a740-4795-ac50-3daf9e5dacfe.jpg?v=1783364223","url":"https:\/\/spokex.com\/products\/sea-to-summit-alpine-down-sleeping-bag","provider":"SX Collective","version":"1.0","type":"link"}