VLF means Extremely Lower Frequency and is the same know-how Utilized in detectors designed for coins, jewellery, and relics. VLF detectors broadcast at frequencies measured in kilohertz starting from 3 kHz to 70 kHz. Listed below are 5 explanations why you would possibly choose a VLF more than a PI http://eurotrucksimulator.phorum.pl/viewtopic.php?p=1524385#1524385