Features:There are 2 standard for your option: 2mm/4mm.This insulation piercing clips is able to contact with insulated wires without cutting or stripping insulation, protect your wire while testing.Pierces insulation on wires from 14 AWG to 22 AWG(0.03" through 0.18" diameter) by rotating the bottom and sliding black spring clip.Wire piercing probe is made of quality plastic, which is sturdy- and will not break easily.Wire piercing clips can be used for automobile repair, equipment repair and appliance repair, convenient for you to finish voltage measurement.Specifications: Material: ABS-Size: 2mm/4mm(optional)Length: approx 9.6cm/4-inchPackage Includes: 1xWire Piercing ProbeNote: Please allow 1-3cm error due to manual measurement. please make sure you do not mind before you bid.Due to the difference between different monitors, the picture may not reflect the actual color of the item.