Ultimate Direction teamed up with ultra runner Anton Krupicka to create the AK Mountain 3. 0 Hydration Vest. Since Anton sticks to a 'less is more' philosophy, this vest is super light and only contains the features you need to carry gear that is completely necessary. A hydration bladder, although clever in design, is inconvenient to refill and becomes a pain when it bounces around on your back. Water bottles are a much more elegant solution, and the AK Race vest allows you to carry two at chest level, with one on each shoulder strap. Here the bottles are free from the bounce caused by running on the trail, and they're easy to grab for drinking and refilling. Behind these holsters lies a harness made of highly breathable knit mono mesh that conforms to your body, and behind that, a stretchy storage compartment comprised of Darlington Power Mesh. In order to carry the necessary gear for more adventurous trail runs, Anton updated the design of the AK by adding dual ice axe loops, trekking pole straps, and a large main back compartment to carry a harness and rappel rope.