Features [Expanded Frequency Range] The meter measures various electromagnetic fields from 50Hz to 20000Hz, capable of detecting cell phones within a 2ft range, providing a comprehensive detecting solution. [Ensure Health] This electromagnetic field radiation detector helps measure radiation levels, identifying devices with high radiation output to prevent prolonged exposure, protecting your health. [Colorful LED Indicators] Featuring 5 LED indicator lights, the magnetic field radiation tester offers clear readings visible in both daylight and darkness, making it convenient to use in different environments. [Versatile Applications] Ideal for testing TVs, computers, microwaves, refrigerators, printers, cell towers, household appliances, ensuring safety and awareness of exposure in various settings. [Portable Design] Compact and lightweight, this electromagnetic radiation tester can easily fit in your pocket or wallet, allowing for convenient using and ensuring easy access whenever needed. Spec: Item Type: Magnetic Field Detector Material: ABS Battery: 9V 6F22 Battery x 1 (Not Included) Detection Range: 0~20+ milliGauss Detection Frequency: 50 60Hz (50-1000Hz ELF), (1000-20000Hz VLF) How to Use: Install the battery, turn on the switch, and use it. Package List: 1 x Magnetic Field Detector 1 x User Manual Package List 1 x Magnetic Field Detector 1 x User Manual