The "Mustang" hydration system boasts many features including an extremely durable 120 oz. collapsible bottle bladder. The bladder is a one-piece, flexible blow molded bottle with an integral threaded neck that can fit a standard M-1 military canteen cap. The hyperflow bite valve delivers a high flow rate when drinking, but drip free when not in use. Bladder is capable of withstanding freezing temperatures. Sanitation is a breeze with our bottle designed bladder, just rinse and air dry. The pack fits comfortably with 2 inch adjustable shoulder and chest straps, quick release buckles, D-ring attachment points and waist strap. The nylon-insulated pack has two 140 cubic inch zippered cargo compartments, one compartment includes integrated organizer for pens and small electronics and MOLLE web system.