Feature: 1. WIDE APPLICATION: EMF ghost detection help measure electromagnetic fields to identify devices that produce high radiation levels and enable users to determine the extent to which exposure is limited. Emf tester is mainly used to test TV, computer, microwave oven, refrigerator, printer, cell tower, low frequency home appliances, ghost hunting and so on 2. COLOR LED INDICATOR: This electromotive force detector ghost hunt has 5 LED indicators that can see readings in the day or in the dark, can be carried in your pocket or purse, which is easy to carry around 3. PROTECT YOUR HEALTH: Measuring the level of an EMF meter radiation detector is designed to prevent the potentially harmful effects of long‑term overexposure to electromagnetic fields, and you can use this EMF detector in your home, office, and other places 4. ACCURATE MEASUREMENT: The ghost detection detector run on a single battery and report EMF measurements in the 5 mGyS range 5. GREATER FREQUENCY RANGE: This electromotive force reader for radiation measure a variety of electromagnetic fields from 50 Hertz to 20,000 Hertz and can detect cell phones within 2 feet Specification: Item Type: EMF Meter Material: ABS Battery: 1 x 9V Battery, Battery Capacity: 800mAh Detection Range: 0~20+milliGauss Detection Frequency: 50/60Hz(50-1000Hz - ELF), (1000-20000Hz - VLF). Package List: 1 x EMF Meter1 x User Manual Note: The battery needs to be replaced when it is dead, and the detector cannot be charged.First, remove the plastic cover with a screwdriver. Then remove the battery and finally just put in a new battery and tighten it again with a screwdriver.