Overview The Sea to Summit Ultra-Sil Dry Bag is an ultralight waterproof storage solution designed for backpacking, cycle touring, travel, and organized packing inside backpacks or duffel bags. Made from bluesignA(R) APPROVED 30D Ultra-Sil CORDURAA(R) nylon, it provides dependable moisture protection while adding very little weight to your gear. The semi-translucent fabric makes it easier to identify contents without opening every bag, while the non-wicking Hypalon roll-top closure, taped seams, and patented Field Repair Buckle create a reliable seal. An oval base helps prevent the bag from rolling away on sloped surfaces and packs efficiently alongside other gear. Best For Backpacking and lightweight camping Travel and luggage organization Cycle touring and bike travel Organizing clothing and gear inside backpacks or duffels Users who prioritize minimum packed weight Key Features Ultra-Lightweight Construction: Made from lightweight 30D Ultra-Sil fabric to provide waterproof storage with minimal added weight. CORDURAA(R) Nylon: Strong 30D nylon fabric provides durability while maintaining an exceptionally light profile. bluesignA(R) APPROVED Fabric: Main fabric meets bluesignA(R) approval requirements. Semi-Translucent Material: Makes it easier to see and identify the contents of each bag without fully unpacking. Roll-Top Closure: Non-wicking Hypalon roll-top creates a reliable closure when properly rolled and secured. Field Repair Buckle: Sea to Summit&';s patented buckle design provides a replaceable closure system for easier field repairs. Taped Seams: Helps keep moisture from entering through stitched areas. Oval Base: Helps prevent the bag from rolling away on sloped surfaces and improves packing efficiency. Slippery Exterior Finish: Helps the dry bag slide easily into and out of tightly packed backpacks and luggage. Specifications Brand: Sea to Summit Product Type: Lightweight Dry Bag Best Use: Backpacking Fabric: 30D Ultra-Sil CORDURAA(R) Nylon Bag Material: 100% Nylon Buckle Material: POM Shape: Oval Hydrostatic Head: 2,000 mm Repair Buckle Size: 15 mm Available Sizes: 3L, 5L, 8L, 13L, 20L, 35L Size, Weight & Dimensions Size Weight Height - Top Rolled 3x; Base L x; W 3L 1.1 oz 8.15 in 5.5 x; 6.7 in 5L 1.1 oz 12.13 in 5.9 x; 6.7 in 8L 1.4 oz 14.49 in 6.8 x; 7.5 in 13L 1.7 oz 17.05 in 7.7 x; 8.7 in 20L 2.0 oz 18.62 in 9.3 x; 10.6 in 35L 2.6 oz 22.24 in 11.2 x; 12.6 in What&';s Included One Sea to Summit Ultra-Sil Dry Bag in the selected size/color FAQs What is the Ultra-Sil Dry Bag made from?It is constructed from lightweight bluesignA(R) APPROVED 30D Ultra-Sil nylon featuring CORDURAA(R) yarns. Can you see through the fabric?The fabric is semi-translucent, making it easier to identify what is stored inside without opening the bag. How does the bag close?It uses a non-wicking Hypalon roll-top closure secured by Sea to Summit&';s patented Field Repair Buckle. Why does it have an oval base?The oval shape helps prevent the bag from rolling away on sloped surfaces and allows it to pack efficiently alongside other gear. What sizes are available?The Ultra-Sil Dry Bag is available in 3L, 5L, 8L, 13L, 20L, and 35L sizes. Each size is sold separately. Care & Maintenance Empty the dry bag after use and allow it to dry completely before long-term storage. Remove dirt, sand, or debris as needed and inspect the roll-top, taped seams, and buckle periodically for wear or damage. Avoid packing sharp objects that could puncture or abrade the lightweight 30D fabric. Expert Insight The Sea to Summit Ultra-Sil Dry Bag is especially useful when every ounce matters. Its extremely light 30D construction, semi-translucent fabric, and smooth exterior make it ideal for organizing clothing and other gear inside a larger backpack or travel bag without adding the bulk of a heavier-duty dry bag.