This product is an electromagnetic field and electric field radiation detector with audible and visual alarm, which is widely used for radiation measurement of household appliances. Note: 1. Due to manual measurement, the size may be slightly different. Thank you for your understanding. 2. Due to different light conditions and different monitors, item color displayed in photos may be showing slightly different from real object. Specifications: Brand: Mastfuyi Model: FY8809 Color: Black & Green Shell Material: ABS Display: LCD Electromagnetic Field Intensity: Measurement Range: 0.1-199.9mG / 0.01-19.99T ( 4Hz~300Hz ) Resolution Ratio: 0.1mG / 0.01T Alarm Threshold: > 4.0mG / > 0.4T Accuracy: 20% Electric Field Intensity: Measurement Range: 1-1999V/M ( 4Hz~3.5Gz ) Resolution Ratio: 1V/M Alarm Threshold: > 40V/M Accuracy: 20% Working Temperature and Humidity: 0~40 / 32~104, 45%~80%RH Storage Temperature and Humidity: -20~60 / -4~140, 45%~80%RH Power Supply: 1 * 6F22 9V Battery ( Not Included ) Item Size: 18.9*5.4*3.5cm / 7.44*2.13*1.38in Net Weight: 128g / 4.51oz Packing Size: 21.5*6.5*4.5cm / 7.44*2.56*1.77in Packing Weight: 170g / 6.00oz Package List: 1 * EMF Meter 1 * Manual ( English )