The Men's Dakine Session Hydration 8L Backpack is a hydration backpack for mountain biking. Hit the trails at speed, tackling hills, features, wayward branches and zipping around curves. This 8L pack is small but mighty, with an included 2L Hydrapak reservoir to keep thirst at bay during all those miles. The 20 mile loops are calling, and the Air Flow backpanel and shoulder straps are breathable for a couple steady hours of pedaling. Stash bike tools, an extra tube, rain jacket and you're ready for some time in the saddle.