Alligator clip

metal clip with long, serrated jaws, used for temporary electrical connection

Alligator clips are toothed clips on the ends of electric wires. They are hinged near the back, making them look like alligator jaws. Sometimes they are also called crocodile clips. Usually those clips are used in measuring to temporarily connect a meter to an electrical circuit or a single component.

Alligator clips come in different colors and sizes