Many Minelab detector's testing low frequency big gold SD GP GPX detectors large coils. 

Dave and myself took out all the recent modded and upgraded detectors for some testing, modded SD2000 test on 1990 mods to new mods and you can see the difference, the new Wolf in Sheep's clothing mod is so quiet but powerful, no external switches or knobs to keep it automatic and simple to operate.
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