The Extech 480836 RF EMF field strength meter monitors RF radiation in the range from 50 MHz to 3.5 GHz. Ideal for cell phones, cell phones, base stations, locating RF hotspots, detecting RF wireless networks (Wi-Fi), detecting RF "electrosmog" and microwave leakage. It features non-directional measurements with 3-channel probe (triaxial), max-hold and average functions and manual storage/recall of up to 99 data sets. There is also an audible alarm with a user-selectable threshold. The scope of delivery includes a 9 V battery and a carrying case.