How to use: 1. To check the voltage, hold the end button and connect the tip to the point you want to check, the display will show the voltage range immediately. 2. To identify the wires, hold the second button ( close to LCD) , when the wire is detected, A spark sign will show on the display area. 3. To check a broken point on a wire, just following the hot wire with spark sign on, when the spark sign disappears, there is a broken point on the wire. It will become handy when you check your holiday lights.