Description: Measuring voltage: AC 90V to AC 1000V Operating temperature: -10 to 50 C Storage temperature: -10 to 50 C Operating Humidity: 80% Pollution index: 2 Cleaning method: wipe with a damp cloth Operating power: 7 batteries * 2 (not included) Specification: Material: Plastic Size: Approx. 152*17*22mm / 5.98x0.67x0.87inch How to use: Non-contact pen, the whole insulation plastic seal, you are in the electricity, the most secure protection, without any risk of electric shock. 1. the pen sensor or detect the voltage, the white handle will be light and beep, it is easy to detect the FireWire, and know which line there is a dangerous voltage. 2. induction pen in the middle of a button, press her, there is a bright red LED will be luminous, can be used when the torch, in the dark workplace, you can do not need to use flashlight to easily complete the line work! Package Includes: 1 Piece of Voltage Tester Pen