EMF detector is a portable healthand field detector, which can detect AC magnetic field,electric field and high-frequency(RF) radiation. It is mainly used to detect and evaluate the impact on human body of non-ionizing electromagnetic field, magnetic field and high-frequency radiation in living and working environment. THREE-COLOR BACKLIGHT ALARM INDICATION: After powering on, select the desired detection function. When the device detects a magnetic field (or electric field, radio frequency, microwave), it will display different backlight colors based on the magnitude of the measured value to alert the user. MULTIPLE MEASUREMENT MODES, ONE-KEY SWITCHING: Press the "FUNC" button to switch between magnetic field measurement (uT), magnetic field measurement (mG), electric field measurement (V/m), and high-frequency measurement(mW/m2) modes. WIDE RANGE OF APPLICATIONS: Suitable for use with household appliances operating in the power frequency range, such as refrigerators, washing machines, dishwashers, vacuum cleaners, electric blankets, televisions, personal computers, and ultrasonic generators. EVERYWHERE IN OUR LIVING ENVIRON-MENT IS FILLED WITH RADIATION: In everyday life, there are many sources of radiation such as microwave ovens, electric fans, and air conditioners that emit radiation. Care 's health and from radiation. Power Supply:AAA 1.5V x 3pcs(Not included batteries) High-definition LCD display Automatic shutdown Colour:Black & Red Material:Plastic Package Contents: 1 * EMF Meter 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.