VLF stands for Really Low Frequency and is the same technology Employed in detectors built for coins, jewelry, and relics. VLF detectors broadcast at frequencies measured in kilohertz ranging from 3 kHz to 70 kHz. Allow me to share five main reasons why you might select a VLF in excess http://forum.446.s1.nabble.com/How-to-Choose-Metal-and-Gold-Detectors-td140733.html