Puncture clips allow the user to provide the precise pressure required to puncture the insulation of various wire types and sizes. design is both cost-effective and convenient, it can bequickly removed to expose the puncture tip for any required sharpening, extending the life of the product. The red and black color-coded barrels providequick circuit identification The test clip offers further convenience with its 'in-line retention'feature. Once the test clips are attached to the leads, the test leads can be removed from the clips for testing in another location. Attach it to the banana plug and then the other end can be hooked onto the insulated wire, by turning the red or black end of the clip the needle pierces the insulation to make contact with the conductor. Probe Tip:4mm Please check as much as possible to make sure the item is what you need. Tips:The product may be updated constantly ,Due To Different Batches, The Actual Product May Have Slight Differences Or Color Differences, Which Does Not Affect Use. Colour:As Shown Material:Plastic Package Contents: 2 x Car Repair Wire Clip Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.