These are the trickest couplers ever made. They feature light weight aluminum bodies with a crush-proof steel nose sleeve. The black sleeve is aluminum and acts as an on/off valve which shuts off pressure while connecting or disconnecting tools or hoses. This means that connections and disconnections are effortless and safe. I like to use this coupler as a tire reseating tool. By pushing it onto a stem and then moving the valve sleeve forward I can give an unseated tire a burst of air and shut it off after it has seated. Not only that, I can borrow an air tool or hose on the trail, race course, or job site and my Super Coupler will most likely accept it since it is compatible with four different types of coupler plugs.