Features Material: 210D ripstop nylon, 210D dobby nylon Volume: [small/medium] 1342 cu in, [medium/large] 1464 cu in Support/Suspension: reACTIV, OpenAir back panel Shoulder Straps: SwingArm Waist Belt: yes, OpenAir Description Product Description Black Diamond's Bolt Backpack is the versatile choice whether you're hiking, bagging summits or hiking into a remote crag for the day. With a 24-liter capacity, the Bolt has enough space for quickdraws, rope, a harness, shoes, and lunch. Its ReActiv suspension system includes shoulder straps and a waist belt that move with you while hiking to provide maximum efficiency, ensure a natural stride, balance load transfers, reduce knee stress, and eliminate sore spots that can be prone to bruising; yeah, it does just about everything. Made with Black Diamond's OpenAir technology, the Bolt's back panel, waist belt, and shoulder straps circulate air to keep you cool in warmer weather. This top-loader has a zippered side access for quickly retrieving layers mid-hike. Black Diamond also equipped the Bolt with an external access hydration sleeve for your own reservoir, attachment loops for trekking poles or ice axes, and multiple pockets at the front, sides, and waist belt for all your electronics, valuables, and snacks (mostly just snacks, though).