Gibbs Ascenders are commonly used by rescue teams as a substitute for prusik cord brake in rope rigging systems and work well under the most adverse conditions, even on muddy or iced ropes. Designed not to slip. Pull tested to 1000lbf (4.44kN).

#1 Free Running: Load must be put on the cam to support the weight of the rope. 7/16 - 1/2" (11-13mm rope).
#2 Spring Loaded: WIth the spring engaged it will support it's own weight with no load on the cam. 7/16 - 1/2" (11-13mm rope). Intended for climbing ropes and pack hauling by mountain climbers and cavers. It is not intended for litter raising or support of more than one person or self bleay.
#3 Spring Loaded: With heavy duty aluminum shell and forged cam. 7/16 - 1/2" rope Intended for Litter raising and load hauling where extra strength is required. Not for self belay by solo climbers.
#4 Spring Loaded: With heavy duty aluminum shell and forged cam. 3/4"