Tree climbing ascenders and descenders come in all types of form from rope to mechanical forms. The mechanical forms include the Petzl Zigzag and the ART SpiderJackboth of which are engineered to improve the speed, control and energy use of the tree climber. Marlow Ropes, Beal and Teufelberger produce excellent friction cord for prusik loops and other climbing knots for the standard way of ascending.
