Features: The test probe with a standard 4mm banana plug test lead connection, it works with most test lead kits in the field. The test probe applications include automotive, industrial, HVAC, electrical, marine and more. Sharp 0.7mm needle tip, they are used for piercing the insulation of wires to allow for automotive electrical measurements without causing damage to the wires. The test probe is suitable for back-probing harness connectors and automotive sensors. Made of high quality stainless steel, copper & PA, durable & sturdy, long time service. Package Includes: 10x Back Probe Pin Specifications: Material: stainless steel+copper+PA Length: approx 7.8cm/3.1in Hole diameter: approx 4mm/0.2in Needle head: 0.7mm note: Please allow 1-3cm error due to manual measurement. pls 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.