Alligator, Crocodile, and Heavy-Duty Test Clips are most often used between an electronic circuit and a measurement device,?providing a temporary electrical connection. Items in this family are spring loaded and contain two jaws with serrated teeth. The types are alligator, battery terminal clamp, bus bar clip, clamp, crocodile, dolphin, geophone, heavy duty, Kelvin, Pee-Wee, and telecom.