100% Nylon Imported 22-liter capacity day pack weighs less than four ounces and packs down to the size of a water bottle Ultra-Sil 30D siliconized Cordura Nylon fabric is waterproof, lightweight and provides an exceptional strength-to-weight ratio Reinforced seams are double-stitched and sealed; unique non-wicking double roll-top closure with quick-release buckle Elasticized reflective compression lacing system secures gear and is ideal for bike commuting Includes attached stuff sack and handy aluminum carabiner; weight 3.9-ounces