Mueller Insulated Large Safety Alligator Clip Insulated large safety alligator clips with nickel plated steel clip and glass filled nylon housing. These safety alligator clips are 82.04mm in length with a jaw opening of 19mm. A sharp tooth in the lower jaw of the clip enables a secure connection when in operation. These safety alligator clips are compatible with all insulated, non-insulated and retractable banana plugs.