The Universal Safety Couplers reduce the possibility of injury or damage from a whipping hose that is disconnected under pressure by remaining connected to the nipple until all downstream air is completely bled off. Perfect for any air drop or work bench, these couplers easily connect under zero pressure with five major interchanges including Automotive, Industrial, Aro, European, and Lincoln. Please note, in 3/8" and 1/2" body sizes, these couplers ONLY connect with Automotive and Industrial interchanges. For high vibration applications, we recommend the use of a whip hose to extend coupler service life.