Features [Accurate Measurement] --- This electromagnetic field radiation detector adopts advanced technology, providing high sensitivity and accuracy, can accurately measure a wide spectrum of EMFs ranging from 50Hz to 20,000Hz. [LED Indicator] --- The LED indicator helps you easily understand the electromagnetic field, which turns dark green for 1 to 2.5mG, green for 2.5 to 5mG, yellow for 5 to 10mG, orange for 10 to 20mG, and red for 20+mG. [Battery Powered] --- This portable EMF detector is powered by a 9V 6F22 battery, making it convenient to use. Made with ABS material, sturdy and resistant to impact. [Easy to Use] --- With just one button, this electromagnetic field radiation tester is easy to operate with one hand, compact and lightweight, allowing for easy pocket storage and carrying. [Wide Application] --- Widely used in ghost hunting and measuring electromagnetic fields, this detector helps identify devices with high radiation and assists users in making decisions to limit exposure. Specification: Item Type: Electromagnetic Field Radiation Detector Material: ABS Model: ER10BB Measurement Range: 0-20+mG Power Supply: 9V 6F22 dry battery x 1 (shipped without battery) Accuracy: 5% Size: Approx. 150x55x30mm/5.9x2.2x1.2in Measurement Frequency: 50 60Hz Working Temperature: 18-49℃ (0-120℉) Package List:1 x Electromagnetic Field Radiation Detector1 x User Manual Package List 1 x Electromagnetic Field Radiation Detector 1 x User Manual