VLF means Very Very low Frequency and is the same technological know-how used in detectors designed for coins, jewelry, and relics. VLF detectors broadcast at frequencies calculated in kilohertz starting from three kHz to 70 kHz. Here's 5 explanations why you may perhaps choose a VLF above a PI In https://latinverge.com/forums/topic/30513/how-to-spot-rare-metals-underground/view/post_id/216537