Designed for use INSIDE a backpack, bike bag, or duffel — not for external/paddle.

3L-8L: 2 ladderlock + 1 SR buckle. 13L-20L: 2 ladderlock + 2 SR buckles (more compression control).

Patented STS Field Repair Buckle — user-replaceable in the field.

Chemical safety verified throughout the supply chain.

Squeeze air OUT for compression · water stays IN — same STS Evac tech.

The Ultralight uses Ultra-Sil 30D CORDURA® — significantly lighter than the Lightweight Compression's 70D: What 30D means: - 30 denier per fiber (vs 70D in Lightweight — over half the thickness) - Even thinner than the Lightweight - UltraSil = STS's proprietary ultra-light fabric technology (same family as DryLite towel) Why "Ultra-Sil" matters: - STS's specially treated nylon for ultralight - High strength-to-weight ratio - Sufficient for internal pack use (no abrasion against external objects) Trade-off matrix: | Aspect | 30D Ultralight | 70D Lightweight | 420D HD | |---|---|---|---| | Weight (20L) | 110 g / 3.9 oz | 160 g / 5.6 oz | 370 g / 13.1 oz | | Hydrostatic Head | 2000 mm | 10,000 mm | 10,000 mm | | Abrasion Resistance | Low (internal only) | Moderate | High | | Tear Strength | Light | Moderate | High | | Best For | Internal pack use | General outdoor | Vehicle / rugged | | Cost | $39.95-$59.95 | $39.95-$59.95 | $59.95-$89.95 | The 30D is durable enough for: - Backpacking (inside a pack) - Internal compression of soft items - Modular backpack organization - Sleeping bag storage inside a duffel or backpack The 30D is NOT appropriate for: - "Paddle sports" or sharp/abrasive elements (per FAQ) - External bike cargo mounting (use Evac Bikepack or HD) - Vehicle/luggage use (use HD) - Heavy loading or sharp contacts

The Ultralight has only 2000mm hydrostatic head vs the 10,000mm of the Lightweight and HD: What 2000mm means: - Lower than the 10,000mm in other Evac products - Sufficient for "storage inside a backpack or duffle" (per STS FAQ) - Not sufficient for direct water exposure (paddle, kayak, submersion) Per FAQ: "Is this dry bag waterproof? The body of the dry bag is waterproof enough (2000+ mm hydrostatic head) for use as storage inside a backpack or duffle. However, for water sports or general, external use we recommend compression dry bags with a higher hydrostatic head/more abrasion and puncture-resistant fabrics." The key insight: - 2000mm = waterproof enough for INTERNAL pack use - Your pack/bag provides additional water protection - The Evac Compression UL is a SECOND layer of waterproofing, not primary Why this matters: - This is the lightest in the line BECAUSE it's the least waterproof - Trade-off: thinner fabric + less coating = less weight, less waterproof - Use it inside other containers (packs, bags) - Don't use as a stand-alone waterproof for paddle sports If you need waterproof + ultralight: - Use Ultralight INSIDE a 100% waterproof outer (pack liner) - The Ultralight keeps gear organized + compressed - The pack liner keeps water out - Combined: ultralight packing + full waterproofing

The Ultralight uses a variable strap configuration by size — a unique design compared to other Evac products: Per STS: "the 3L, 5L and 8L include two ladderlock straps and one side-release buckle strap while the 13L and 20L include two ladderlock straps and two side-release buckle straps for maximum compression control on larger loads." Why different per size: - Smaller bags (3L, 5L, 8L): Less compression needed — 1 SR buckle is sufficient (faster open) - Larger bags (13L, 20L): More compression control needed — 2 SR buckles for finer adjustment Ladderlock Buckles (both sizes): - 2 per bag - Permanent tension (wrap around and pull through) - Stay tight without holding them - Main compression force Side-Release Buckles: - 1 small / 2 large - Quick-release (snap apart) - Easier to open without re-tensioning ladderlock - For accessing contents without fully unthreading Why this matters: - More compression control = denser pack - But not heavy (just plastic buckles) - Trade-off between compression power + ease of access Practical: - 13L+ bags: 2 SR buckles = adjust each side independently - Smaller bags: 1 SR buckle = faster open

Per STS FAQ: "this dry bag is for use as storage inside a backpack or duffle. However, for water sports or general, external use we recommend compression dry bags with a higher hydrostatic head/more abrasion and puncture-resistant fabrics." What "internal use" means: - Lives INSIDE a backpack, duffel, or larger container - Protected from external abrasion by the outer container - Touches soft items only (clothes, sleeping bag) - Not exposed to weather independently What's wrong with external use: - 30D fabric too thin for sharp/abrasive contact - 2000mm hydrostatic not enough for direct rain - Lightweight buckle attachment = not for vehicle straps Use examples INTERNAL: - Inside your hiking backpack - Inside your duffel for travel - Inside your pannier - Inside your framebag (bikepacking) Use examples for OTHER Evac products (NOT this one): - Bike cargo cage mounting (Evac Bikepack Set) - Vehicle mounting (HD, Compression HD) - Paddle sports (Lightweight) - Submersion anywhere (Heavy Duty)

Same STS evac Fabric at the base across all Evac products: Per STS: "Waterproof and air-permeable Evac fabric base allows air to be pushed out but water can't get in" Why UL has the same Evac base: - Compression works only if air can escape - The Evac base enables the compression feature - Without Evac = sealed bag = puffy bag = no compression For UL specifically: - The thin 30D fabric needs the Evac base for performance - Even with thin fabric, compression works - Air gets pushed out + water can't get in - Reliable technology across the line Limitations: - Air goes BOTH directions (per FAQ — not one-way) - Compression requires tight surrounding packing - For sustained compression, use with a snug pack

Per STS FAQ: "Does this bag work for modular packing in a backpack? Yes! Use these bags for all compressible items. First, squeeze the air out, then pack the dry bag into a tight space in your bag or pack so it does not draw itself full of air again. It works wonders on sleeping bags and insulated clothing." Modular packing setup (UL optimized): - 3L = down jacket - 5L = base layers + socks - 8L = sleeping bag - 13L = sleeping bag + clothing - 20L = bulk items (multiple) Each bag goes into its own compartment: - Sleeping bag at bottom - Clothing in middle - Accessories up top - Each bag squeezes air + compresses independently The UL's advantage for modular packing: - Lightest fabrics (per size) - All 5 sizes work together - Compression works inside other bags

Five Evac products now built: | Aspect | Evac Ultralight Compression (this) | Evac Lightweight Compression | Evac Compression HD | Evac Lightweight Dry Bag | Evac Bikepack Set | |---|---|---|---|---|---| | Type | Compression Sack | Compression Sack | Compression Sack | Dry Bag | Storage/Packs | | Body Fabric | 30D Ultra-Sil CORDURA® | 70D recycled nylon | 420D TPU-laminated | 70D recycled nylon | 420D HD | | Hydrostatic Head | 2000 mm | 10,000 mm | 10,000 mm | 10,000 mm | 10,000 mm | | Use Position | INTERNAL only | General | Vehicle/rugged | General | Bike cargo cage | | Compression | Yes (3-strap or 4-strap) | Yes (4-strap) | Yes (4-strap) | Manual only (no straps) | No | | Weight (20L) | 110 g / 3.9 oz | 160 g / 5.6 oz | 370 g / 13.1 oz | 95 g / 3.4 oz | 333 g / 11.7 oz (set) | | Shape | Round | Round | Oval | Oval | Oval | | Strap Config | 3L-8L: 2+1 · 13L-20L: 2+2 | 2+2 | 2+2 | Manual only | N/A | | Sizes | 3L-20L (5) | 5L-35L (5) | 8L-35L (4) | 3L-35L (6) | 2 × 3.7L | | Colors | High Rise + Blue Atoll | Turkish Tile + High Rise | Beluga | Beluga + Turkish Tile | Beluga + Turkish Tile | | Recycled | No (Ultra-Sil trade-off) | Yes (100% pre-consumer) | No | Yes (100%) | No | | Price (largest) | $59.95 (20L) | $59.95 (35L) | $89.95 (35L) | $49.95 (35L) | $110 (set) | | Best For | Ultralight internal pack use | General compression | Rugged vehicle compression | Simple dry storage | Bikepacking | Choose Ultralight Compression (this) for: - Maximum weight savings - Internal pack / duffel / pannier use - Modular backpack organization - Soft items only (no sharp contact) Choose Lightweight Compression for: - Same weight class + recycled material - External outdoor use (more waterproof) - Paddle sports (per FAQ recommendation) Choose HD Compression for: - Motorcycling, snowmobiling, kayak - External rugged storage - Highest durability

Backpacking (PRIMARY): - Internal pack use - Modular organization - Smallest + lightest in the line - Multiple bags for full kit Bikepacking (internal): - Inside frame bags - Inside handlebar rolls - For cargo cage use, see Evac Bikepack Set instead Travel / Duffel Organization: - Inside luggage for clothing + soft items - Color-coded by category - Modular packing Packrafting (per FAQ): - Inside the packraft's dry hatch - Lightweight padding - Modular categories NOT for: - Paddle sports (per FAQ: "Featherweight fabrics are not appropriate for the sharp or abrasive elements in water sports. We recommend our Lightweight Dry Bags for general paddle use.") - External bike cargo (use the Evac Bikepack Set) - Vehicle/rugged (use HD) Modular Backpack System: - Sleep bag in 8L or 13L - Clothes in 8L (separate layers) - Puffy jacket in 3L or 5L - All inside the same pack

STS Field Repair Buckle (15mm, replacement): - Same part as other Evac products - Compatible with HD + Lightweight + UL Backpacking Pack with Internal Frame: - Use UL bags stacked inside - Compression bands on the outer pack Duffel Bag: - Use UL bags for organized clothing - Compression maintains pack density Sleeping Bag Stuff Sack: - Replace heavier stuff sack with UL - Lighter + still compressible TSA Locks: - For luggage (UL bags can be locked) Patch Kit: - Tenacious Tape for field repairs Bungee Cords: - For external compression reinforcement - Wrap packs tightly for sustained compression