Enduro Hydration Backpack Black. Hentyâ??s Enduro Backpack is the ultimate hydration kit for cyclists, to keep you energised, ventilated and hydrated. The Enduro acts as a tool belt for all the essentials you need to hand. A water bladder (not included) is positioned as close as possible to your center of gravity, giving you freedom and agility. There are plenty of pockets and webbing for storage and easy access while youâ??re on the move. The innovative design of the Enduro gives you ventilation where it counts, minimizing sweaty back syndrome.