The Dry Sack is a compression stuff sack that features Air Control. Air control is a waterproof air permeable fabric, which allows you to compress the air out and doesn't let water in. This high-tech fabric gives you the ability to compress the contents while maintaining its waterproof integrity fully. The Dry Sack is the perfect compression stuff sack for wet environments (not submersible). FeaturesWaterproof compression stuff sackAir control bottom fabric allows air to be pushed out70D nylon ripstop sides with waterproof coatingWaterproof taped seamsBottom handleBartacked stress pointsStrong and durable nylon webbing 10LCapacity 10L / 615 in^3Dimensions 16" L x 7" DWeight 4.8 oz. 20LCapacity 20L / 1220 in^3Dimensions 20" L x 9" DWeight 6.4 oz. 35LCapacity 35L / 2185 in^3Dimensions 23" L x 11" DWeight 7.2 oz. 45LCapacity 45L / 2827 in^3Dimensions 25" L x 12" DWeight 8 oz.