This probe pen is perfect for checking circuits, fuses, switches and wiring on automobiles, trailers, boats, motorcycles and other low voltage systems. Connect the alligator clamp to the ground, then take the probe to test circuit. If the indicator light is on, there is electricity. Handle is made of plastic and the hardened & tempered carbon steel probe is chrome plated. The steel probe easily pierces wire insulation to check circuitry. Light in handle glows when circuit connection is complete. Test a range of circuits ranging from 6V to 24V. Light weight design and super convenient to bring with. Colour:red Material:plastic Package Contents: 2 X Circuit Tester 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.