I do what I can to foster competition that develops alternatives to the all too common VLF detector. There are plenty of options out there, but in my opinion they all weigh too much or cost too much. Usually both.   I envision people out there with a popular VLF metal detector for beach, relic, or gold detecting. These machines all sell for around $700 and weigh 2.5 - 3.9 lbs. Perhaps they would like to add a ground balancing PI (GBPI) to what they have. I think that for "normal people"