Bimodule Synchronous Test - EMF meters can test both radiations in electric field and magnetic field at the same time for precise result. Sound and Light Alarm - Radiation detectors will assess the test result and it will automatically alarm when it's over the safe value. Alarm Threshold: Electric: 40V or m Magnetic: 0.4T Ecofriendly and - USB rechargeable. Portable and simple design makes digital radiation testers are easy to carry around and do field measurement. Data-Locking and Backlight - Press one botton to lock the data and clear display with blue bakclight allow you to easily read results. Accuracy: 1V or m for Electric, 0.01T for Magnetic. Measure Temperature - Swicthable temperature units ( and ). 0C-50C Colour: black Material: ABS plastic Size: about 133 x 60 x 25mm Package Contents: 1 x electromagnetic radiation detector 1 x USB cable 1 x English manual Only the above package content, other products are not included. Note: Light 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.