#2 on this list
Drawstring
Hyperlite Mountain Gear
The Hyperlite Mountain Gear Drawstring sack is tailored for ultralight hikers who prioritize minimal base weight and durable organization over mechanical compression. Built from Dyneema Composite Fabric (DCF), it serves as a featherweight organizer for ditty gear, electronics, spare socks, or cook systems, offering near-weightless utility inside an already protected backpack. Unlike traditional nylon pouches that absorb water when wet, DCF is inherently hydrophobic and naturally resistant to stretching or tearing. Independent reviewers frequently commend its semi-translucent nature, which allows you to identify contents without having to untie the cord and dump out the interior. The simple micro-cord closure with a tiny cord lock operates smoothly with cold or gloved hands. Because the top opening uses a simple cinched drawstring, the opening does not create a watertight seal. It shields your items from dirt and light splashes inside a pack liner, but it will not protect sensitive gear if dropped into a creek or packed in a flooded compartment. For general trail organization where ounces matter, it represents one of the lightest dependable sacks on the market. **Highlights** - Built from high-strength Dyneema Composite Fabric - Extremely low tare weight (approximately 11 grams for a 4-liter sack) - Translucent fabric allows easy identification of internal items - Non-absorbent material stays dry and cleans easily - Wide variety of smaller capacities ranging from 0.3 to 13 liters **Watch-outs** - Drawstring closure is not waterproof or submersible - High cost per liter compared to standard nylon utility pouches
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#3 on this list
Ultra-Sil Drysack
Sea to Summit
The Sea to Summit Ultra-Sil Drysack targets hikers, paddlers, and adventure travelers seeking dependable moisture protection without adding substantial base weight. Engineered with siliconized Cordura nylon and fully taped seams, it is designed to keep apparel, insulation, and electronics safe from pack leaks, heavy rainstorms, and damp camp environments. Reviewers and long-distance hikers praise the fabric's slick finish, which makes packing and retrieving tightly wedged gear from deep inside a pack bag relatively painless. The Hypalon roll-top closure stiffens the seal, rolling down smoothly to create a reliable barrier against splash and torrential rain. Unlike thick vinyl river bags, the Ultra-Sil material compresses effortlessly around soft items, eliminating awkward stiff edges. However, because the fabric is thin and prioritizes packability, it requires care around sharp objects such as tent stakes, stove edges, or coarse tools. It is also rated for non-submerged weather protection, meaning it is not intended for prolonged underwater submersion or rigorous whitewater use without an outer protective shell. As an internal pack liner or modular organizer, it remains a proven staple. **Highlights** - Lightweight 30D Ultra-Sil Cordura nylon with PU inner coating - Fully factory-taped seams for dependable rain protection - Hypalon roll-top closure with field-replaceable buckle - Slippery outer finish slides smoothly into crowded packs - Available in varied colors for easy organization **Watch-outs** - Thin fabric can puncture if packed against sharp hardware - Not designed or rated for full, prolonged underwater submersion
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Specs side by side
| Spec | Drawstring | Ultra-Sil Drysack |
|---|---|---|
| Primary Material | Dyneema Composite Fabric (DCF) | — |
| Weight (4 L) | 11 g (0.39 oz) | — |
| Volume Range | 0.3 L to 13 L | — |
| Closure Style | Micro-drawstring with mini cord lock | — |
| Water Resistance | Water-resistant fabric (unsealed top) | Weatherproof and splashproof (non-submersible) |
| MSRP | Around $31 | — |
| Fabric | — | 30D diamond ripstop Cordura nylon |
| Coatings | — | Siliconized exterior, polyurethane interior |
| Seams | — | Fully factory taped and sealed |
| Closure | — | Hypalon roll-top with repair buckle |
| Packing Role | — | Internal pack organization and dry hatch storage |
What our reviewers liked and didn't
Drawstring
- Extremely lightweight at roughly 11 grams for a 4-liter capacity
- Translucent Dyneema fabric makes identifying packed gear effortless
- Inherently hydrophobic fabric will not absorb water or gain weight
- High tensile strength resists blowing out under heavy internal strain
- Drawstring closure will not prevent water entry if dropped or submerged
- Significantly more expensive than traditional nylon utility sacks
- Can develop small pinholes over time if packed against sharp metal tools
Ultra-Sil Drysack
- Slick exterior slides effortlessly into tightly packed backpacks
- Field-replaceable buckle allows easy trailside hardware repairs
- Excellent weight-to-weatherproofing ratio for internal pack storage
- Translucent fabric assists in locating gear without opening the bag
- 30D fabric is vulnerable to punctures from sharp camp kitchen items
- Not rated for prolonged underwater submersion or whitewater deck use
- Requires manual air purge before rolling since fabric is non-breathable
Prices change constantly — the figure shown is the last verified catalog price, and the buy buttons always go to the current listing.