1.Puncture clips allow the to the precise pressure required to puncture the insulation of various wire types and sizes.2. design is both cost-effective and convenient, it can bequickly removed to the puncture tip for any required sharpening, extending the life of the product and eliminating the need to completely replace the test clip as with other models on the market.3.The red and black color-coded providequick circuit identification and the bright yellowbody is easy to locate in low light conditions.4.The test clip offers further with 'in-line retention'feature. the test clips are attached to the leads, the test leads can be removed from the clips for testing in another location.5.Use: 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 sharp needle pierces the insulation to make contact with the conductor.The puncture probe measures voltage with a voltmeter without cutting stripping the outer layer of insulationColour:yellow+redMaterial:plasticPackage Contents:4 x Puncture probe2 x Banana socket (multimeter lead) Multimeter lead