International Safety Components, or ISC, is a global provider for high rise window cleaning gear and other at-height jobs. This backup device is made specifically for 7/16 rope. The ISC Rope Grab is unique in the way it uses rotational breaking to stop in case of a fall, called ‘self-braking” (as opposed to self trailing). This makes it a locking device. For a high rise window cleaner, this means that the ISC Red will trail normally while ascending up a rope. It will “self-brake” in the spot that you last placed it, which is handy for minimizing fall distance. To descend, pull the tow line to keep the rotational brake from engaging. If there were to be a fall while using the tow line to descend, the tow line comes off of the device because of the "popper", causing the device to lock. This is called the “popper” because it pops out of the device, keeping the user from holding it open in panic. Note that in a rescue situation, the Red relies on being able to rotate the rope to brake. If there is too much tension on the rope below the device, it could fail to engage. Make sure to only use it on rope with plenty of slack underneath.