Is what I have. That is designed for a wetbox and shoots thru the hull fine. Your R209 is the same transducer in a different design housing. I would reckon if you build a wet box to contain it you should be able to get it to work as an in hull unit. Try it first. make sure there is some water in the hull, push the tranni down the hull and see what the reading is like. Remember thou your R209 needs to be wet to disperse heat so dont run too long. Im not sure what the water proofing is like at the cable entry so take care of that too