Weaver designed this chest harness to help advance an ascender or SRT work positioning device like the Rope Runner, Rope Wrench, or Unicender up the rope while you ascend. By keeping your climbing system close to your chest while ascending slack can be kept at a minimum reducing the shock load potential. The chest harness is adjustable around the chest and is capable of fitting many different body types. The large center attachment point makes connections quick and easy while on the ground or climbing. Not for primary life support.