Hi,   I determined that Garrett Infinium DD (not mono) coils work with the Garrett ATX. That opened the door for some kind of hip or chest mount. But the control box is large enough and with the handle sticking out not really working out the way I wanted in that regard.   A nice thing about the ATX is it retains all settings when switched off. So in any location it is just set and forget. The headphones have adjustable volume controls.   I went with backpack mount. I got a cheap but