VLF stands for Quite Small Frequency and is similar technology Employed in detectors developed for cash, jewellery, and relics. VLF detectors broadcast at frequencies calculated in kilohertz starting from three kHz to 70 kHz. Here i will discuss five explanation why you could possibly select a VLF over a PI http://hotel-golebiewski.phorum.pl/viewtopic.php?p=870910#870910