Osprey's Katari 3 is a stripped down mountain biking pack, perfect for traveling lightly on the trail. An included 2.5-liter Hydraulics reservoir delivers convenient hydration while you ride. There's enough room for small essentials like a pair of gloves or a multi-tool in the protected stash pocket. Adjustable sternum straps ensure a secure fit, and the mesh-covered foam backpanel keeps things comfortable and well-ventilated. Dual side stretch mesh pockets keep beverages within arm's reach Protected pocket for easy stashing of layers and other items Included 2.5 L reservoir for convenient hydration on the trail Summer 2021 product Equipped With Hydraulics Osprey’s Hydraulics reservoir system features thermoplastic polyurethane (TPU) construction, and is entirely BPA-, phthalate-, and lead-free. The wide-mouth opening makes filling and cleaning easy, while their patented QuickConnect hose assures a reliable and convenient connection. Blaster bite valves are designed to provide high-volume flow, and the magnetic harness clip ensures secure and accessible valve placement. AirScape The AirScape system by Osprey utilizes 3D foam backpanels to keep the pack close to your body, forming a stable, secure fit. The panels are highly ventilated to prevent excess perspiration, and the foam adheres to your shape for long-term comfort. With six inches of adjustability, the AirScape system is designed to optimize the fit for a range of body types and sizes.