Find circuit breaker or circuit fuse quickly and accurately. Sensitivity can be adjusted through the ON/OFF switch. The operator can determine the status of circuit connection according to the 3 LEDs. NCV indicator light is only for UT25B. Support GFCI test on socket. The receiver is powered by a 9V battery(not included). The transmitter works on 110-125V. Receiver:Type: UT25A Operating Voltage: 90-120V Operating Frequency: 50-60Hz Operating Temperature: 5C-40C Power Supply: 1 x 9V Type 1604/6F22 Battery(not included) Transmitter: Working Voltage: 110-125V Operating Frequency: 50-60Hz Fuse: 1A, 250V, Note: Installation guide not included, we strongly recommend you professional installation. 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:Red Material:plastic Package Contents: 1 x Circuit Breaker Finder(Receiver) 1 x Socket Tester(Transmitter) 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.