Dual Testing Functions: the EMF meter can accurately detect and measure the electric field radiation and magnetic field emission at the same time. It also can measure the environment temperature(/) Audible and Visual Dual Alarm: if the tested value exceeds the preset alarm value, it will produce sound and light alarm signal immediately Wide Detecting Frequency & Measurement Range: 20Hz~300Hz magnetic field and 20Hz~3500MHz electric field of the working frequency range; 0.01~199.9T(0.1~1999mG) magnetic field and 0~1999V/m electric Field of measuring range User-friendly Design: soft operating buttons for the alarm value setting, MAX/AVG value switching, and units conversion, the mini pocket size EMF tester is just powered by 3pcs AAA batteries, which makes it convenient for using and carrying High Precision & Sensitivity: reliable for measuring electric and magnetic field radiation of mobile phones, hairdryers, computers, TV, printer, attendance machine, refrigerator, etc. Specifications: Material: ABS Magnetic Field Strength Range: 0.01~199.9T(0.1~1999mG) Electric Field Strength Range: 0~1999V/m Magnetic Field Strength Resolution: 0.01T/0.01mG Electric Field Strength Resolution: 1V/m Magnetic Field Strength Frequency Range: 20Hz~300Hz Electric Field Strength Frequency Range: 20Hz~3500MHz Temperature Measurement Range: -10~50 Temperature Resolution: 0.1 Power Supply: 3 * 1.5V AAA battery (NOT included) Item Size: 130 * 50 * 27mm / 5.12 * 1.97 * 1.06in Item Weight: 85g / 2.99oz Package included: 1 x EMF Tester 1 x English User Manual