Designed for people with EHS, this easy to use device provides reliable detection of RF between 200 MHz and 8 GHz. This is so easy, that no technical experience is required to use it, or interpret the readings. Four simple lights provide detection of RF levels as slight, moderate, high, or extreme. The only control is a switch on the right side turns the device power and sound on or off. It’s even designed to produce extra-low emissions from the internal electronics! Includes hard-shell molle case, Building Biology Guidlines sheet, instruciton manual, and certificate of calibration. Requires 2 AAA batteries (included). 2 year warranty.