VLF stands for Pretty Reduced Frequency and is similar technological know-how used in detectors designed for cash, jewelry, and relics. VLF detectors broadcast at frequencies calculated in kilohertz ranging from 3 kHz to 70 kHz. Here are five reasons why you could decide on a VLF around a PI Next, http://nec.phorum.pl/viewtopic.php?p=753869#753869