ISC D4 Rescue Belay Descender

The  D4 Pro Work/Rescue Belay 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 has a 240kg (500lbs) Working load limit which means it is suitable for two-man rescue, without the need for the creation of extra friction. This is a true panic stop device rather than a panic brake device. The difference is that once the panic stop is activated, no other force must be applied to the device. A panic brake style device requires a force input to continue the braking function. Can be used for progress capture in hauling systems and allows rapid conversion between raising and lower.