The D4TM is a double stop device with auto-lock function (activated when the operator releases its handle) and panic brake that does not react with normal use. The D4 cam is made of super hard stainless steel, which is abrasion resistant and corrosion resistant. D4 complies with CE, NFPA T, and ANSI Z359.4 and is used in rope access and rescue markets around the world that normally uses 10.5mm/11mm rope. The D4 Descender features a unique and innovative progressive cam action that allows you to control at low and high speeds. The progressive cam is a mechanism that allows one cam to run inside the another. The D4 also makes the rope backfeeding easy, so it can be used for smooth climbing or emergencies (if used as part of a 2:1 "Z-Rig" rigg). The D4 has a rated load of 240 kg and is a true work/rescue descender. You do not need to add friction to achieve this load, but for more control in belay applications, adding friction is effective. Minimum user weight is 132 lbs (60 kg). Technical Information Supported Rope Diameter (mm): 10.5-11.5mm (7/16") Panic Brake Capacity 2 (WLL) Working Load Limit (kg) 240 (WLL) Working Load Limit (lbs) 529 ANSI Standards Standards Standards Standards Serial Number Standard Equipment EZYiDA Compliance Cam Material Stainless Steel Finish Anodized Certified EN1284 1. - ANSI Z. Meets requirements of 359 and NFPA1983