Designed to do it all-and hold just enough gear-the Siskin 12 is a mountain biking pack with many of the high-performing features you'd expect from Osprey. The mesh-covered AirScape backpanel provides excellent ventilation and maximum range of motion-go ahead, get sendy. A LidLock attachment on the front of the pack can store a standard size helmet while side compression straps expand to hold a full face helmet. The main U-zip compartment houses organization pockets for your bike tools and room for a layer, a sandwich, or some light mountain bike padding. Rolled, soft-edge shoulder straps keep the pack stable over technical terrain and ensure no pinching points when full. A dedicated compartment holds an included 2.5-liter reservoir and zippered hipbelt pockets provide easy access to bars during the ride or a bottle opener afterwards.