PowrHolds are a revolutionary grip strength trainer developed by climbers for climbers.  Pair with the set to make the most transportable finger trainer for climbing.  By adjusting the position of the rope you can change the angle of your grip, challenging yourself by simulating a variety of rock climbing slopes.  Comes with magnetic shims to adjust the depth of your grip, and has a specialized texture that is skin friendly while simulating rock surfaces.  These handle attachments can also be used with free-weights and cable machines with their easily attached paracord and carabiner.