ISC D4 Industrial Descender - Professional Rope Descending Device for Climbing, Rescue & Work at Height - Black (Ideal for Rock Climbing, Construction & Emergency Situations)

The D4 Work/Rescue Descender features a unique and innovative cam action, which offers precise control at slow or fast speeds. The progressive cam works by way of one cam operating inside another cam. The D4 is the only ANSI certified descender on the market today.