Unlike other devices on the market, the El Diablo can be used with either the right or left hand. There is no guessing which way to put the device on the carabiner to use it properly. The El Diablo will not allow the rope to slide up and lock off. The El Diablo can be used on either single or double ropes for rappelling. The El Diablo does not have to be removed from the carabiner in order to attach the rope. This pays off big when working at height and there is fear of dropping the product. Due to the unique design, there are a number of different ways to use this device.