Yeah, when are they going to come out with a unit you can use in the rain/shallow water without the worry of frying your circuitry?
Currently, we have two well known options.
That leaves White's and Fisher/FT up to bat.
It's a 9 function harbor Freight metal detector. I made the frame out of Pvc pipe . I installed the guts inside of a 6 dollar wet box from Walmart. the Pvc frame comes apart in 3 pieces so I can stuff it in a backpack and go on a adventure lol. I would not go diving with it but it's pretty water tight.