Professional Runner Peter Bakwin was the catalyst for the design of the Ultimate Directions PB Adventure 3. 0 Hydration Vest. After years of creating his own packs, Peter teamed up with Ultimate Direction to create the high capacity, bottles up front running pack he wanted. Like many runners, Peter found that water bottles were a much more elegant solution to hydration bladders, which tend to slosh around and make it hard to refill on the fly. As a result, the Adventure Vest touts a bottle holster on each shoulder strap, which locates your hydration where it's easy to grab and quick to refill. Behind these holsters lies a harness made of light, flexible, and breathable knit mono mesh material. Because of the direct integration of the eight liter mesh compartment and the carrying harness, the PB has a seamless feeling that you'll swear is an extension of your own body. You might be asking yourself where the PB Adventure 3. 0 differs from earlier versions of the pack, and while much of the pack remains the same, the 3. 0 now includes ice axe loops, trekking pole straps, and increased capacity.