ISC D4 Work/Rescue Descender


The D4 Descender by ISC is a double-stop device with an auto-lock function and a reliable panic brake for added safety. Crafted from super hard solid stainless steel, it’s built to withstand wear and corrosion.

Its innovative progressive cam action provides precise control at slow or fast speeds, and its design allows for easy rope back-feeding for smooth ascending or emergency hauling.

With a rated load of 240kg, it’s a dependable choice for Work/Rescue scenarios. While additional friction isn’t necessary, it can be added for enhanced control, especially in belay applications. Versatile and reliable, the D4 accommodates users weighing a minimum of 60kg.


  • Individual serial numbering
  • EZYiD available


  • Compatible with rope diameter: 10.5-11.5mm
  • Panic brake: Yes
  • Number of persons: 2
  • Working Load Limit: 240kg
  • Cam material: Stainless Steel
  • Finish: Anodised
  • Approved Standards: EN12841, ANSI Z359 and NFPA 1983
  • 5kN Slip Load
  • Max User Weight: 240kg

Download: Technical Datasheet

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