Excal 1000, Excal II, Sovereign GT, CZ-20, Tiger Shark, Tejon, GTI 1500, Surfmaster Pulse, CZ6a, DFX, AT PRO, Fisher 1235, Surf PI Pro, 1280-X, many more because I enjoy learning them. New Garrett Ca
In my opinion, the AT Pro is best used in pro mode. The key to the machine or any machine for that matter is to learn to hunt by the tones. I sometimes use it on the dry sand (only) area of a beach, for transition and water; a Pulse machine.