Guide to Alligator Clips

Multiple needles are often referred to as a bed of nails, needle clusters or nail bunch and can have a range of needle numbers. Needle clusters are recommended on smaller gauge cables, as it increases the reliability of making a positive connection since a single needle may miss the internal wire conductor. An insulation-piercing connector (also referred to as an insulation-piercing clip, insulation displacement connector, piercing probe, or wire tap) is often constructed as a standalone connector or adapter. The piercing connector has a needle or multiple needles that pierce the wire’s outer insulation jacket to access the wire’s internal (single or multi) conductor for testing. By activating the needle(s) upon wire contact, diagnostic testing is able to occur with an instant connection created for DMMs (digital multimeters), safety analyzers, circuits/boards, or other testing equipment.

This variation of an alligator clip has piercing spikes in the teeth to connect to both bare and insulated wires. The benefit is that they can be used on insulated wires without having to strip the insulation off,  connecting anywhere along the wire. These type of clips are used mainly by the telephone industry as well as by anyone needing to take a measurement without stripping the wire insulation. Telecom clips are also called Popper clips.