Going on a long hike or bike ride? Our Hydration Backpack Cooler is now on sale! Its insulated water pack keeps your needed fluids cool on your hot rides. It includes a two-liter reservoir, that's 67 ounces, which is enough for a 4 hour ride on a hot day. It uses the tried and true tubing and mouth piece for for quick drinks on the fly. It is also made of nylon ripstop and reflective trim for those who can't stop riding when the sun goes down.