Industrial spring break device,usually used in garage door or industrial door ,sectional door,overhead door etc..

spring failure safety device

when the cable break,it protects and adjusts door operation,in order to stop the door drop..

So it works for safety,very important for garage door system safety protection.
Garage door can be dangerous task. Garage door springs and cables are under
extreme tension and require appropriate safety precautions. Working with
garage doors and openers could result in personal injury or death. We recommend all installations,
repairs, adjustments, and removals on garage doors be made by a qualified
garage door technician. Any attempts to install, repair, replace, adjust garage
doors or openers are done at your risk.