ISC D4 Descender

 ISC D4 Work/Rescue Descender (10.5-11.5mm Rope)

The D4™ is a double-stop device with an auto-lock function (which is activated whenever the operator lets go of the handle) and a panic brake which is not overly sensitive in normal use. 

The D4 cam is made from a super hard solid Stainless Steel and is highly wear and corrosion resistant. The D4 is compliant with CE Standards, NFPA T and ANSI Z359.4 for the worldwide Rope Access and Rescue markets which typically use 10.5mm/11.5mm ropes.

The D4 Descender features a unique and innovative progressive cam action, which offers control at slow or fast speeds. The progressive cam works by way of one cam operating inside another cam. It is also easy to back-feed the rope through the D4 and therefore it can be used for smooth ascending or for emergency hauling (when used as part of a 2:1 ‘Z-rig’).

The D4 has a rated load of 240kg (529lb), making it a true Work/ Rescue Descenders. It is not necessary to build in additional friction to achieve these loads, although it can be useful to do so, for an even higher degree of control in Belay applications. The minimum user weight for these devices is 60kg (132lb).

EN12841, ANSI Z359, NFPA 1983- meets the requirements of EN341

Compatible w/ Rope Diameter (mm): 10.5-11.5mm (7/16")

Panic Brake: Yes

Number of Persons: 2

(SWL) Safe Working Load: 529 lbs.

ANSI Compliant Version: As Standard

Serial Numbering: As Standard

Max User Weight > 240kg (530lbs)

5kN Slip load

User Instruction Manuel

Generic User Manual