ISC D4 Descender

The ISC D4 Descender is a robust and versatile descender with auto-lock and panic brake, perfect for rescue operations, rope access, and work positioning. Manufactured with high-quality stainless steel for extreme durability and corrosion resistance.

Features

• Unique progressive cam action: A cam within a cam provides precise control at both low and high speeds.
• Auto-locking: Automatically engages when the handle is released.
• Panic brake: Prevents unintentional rapid descents, but not overly sensitive in normal use.
• 360° rotatable handle: Made of aluminum with a grip coating, clear positions with an audible "click" for secure feedback.
• Easy back-feeding: Allows for smooth ascent or emergency descent (e.g., in a 2:1 Z-rig).
• No plastic in the handle: All-metal construction for maximum durability.
• Serial numbering: Standard for traceability.
• For two persons: Suitable for two-person rescue.
• No extra friction needed: Achieves nominal load without additions.

Technical Specifications

• Compatible rope diameter: 10.5–11.5 mm (7/16")
• Working Load Limit (WLL): 240 kg (529 lbs)
• Max user weight: 240 kg (529 lbs)
• Min user weight: 60 kg (132 lbs)
• Slippage load: 5 kN
• Cam material: Stainless steel (super-hard, wear and corrosion-resistant)
• Finish: Anodized
• Number of persons: 2
• ANSI compliant: As standard

Standards and Certifications

• EN12841 (Type C), meets EN341
• ANSI Z359.4
• NFPA 1983 (Technical Use)

Demo: Watch video here