Nylon Teardrop-shaped design with spacious main compartment Internal MP3 player pouch and rubberized headphone port Weather resistant protective over flap Volume: 1000 cu.in. / 16L Weight: 2.7 lbs. 1000-Denier water and abrasion resistant light-weight ballistic nylon fabric Main compartment: 18" (High) Tapers from 16" wide at base to 6" wide at top. Total Capacity : Over 1600 cu. in. Hydration (two) : Up to a 100oz/3L CamelBak reservoir (rear hydration pocket), 32oz/1L Nalgene (side pouch) (sold separately) Shoulder Support : Wide shoulder strap (tapers from 4.5" to 3") Waist Support : Concealable 1.5" waist strap