The 4L Aux Pox (V2) mounts on the back and/or front of the Backcountry 25 Pannier, or on the back of each leg of the Reckless 80L or Reckless 40L (V4.0), using 5 bolts, washers, and tee nuts. It consists of a harness and a removable, welded-seam, roll-top drybag. The harness can also be used without the included drybag, for things like fuel bottles, a hydration reservoir, or a tool roll. The V2 features velcro closure hatch door for the MSR dromedary nozzle at the bottom of the harness. There's Hypalon armor along the bottom to the edge to protect against abrasion and reflective panels on the outer face for visibility.