my transducer is encased in a silicone puck. mounted directly below the first thwart in front of the stern seat with a dab of silicone. have had no probs. the first time i made the puck, there were bubbles in the silicone. decided to scrap it and start again.     love to watch the bottom contour. it's so great to be moving over deep water and all of a sudden in the middle of nowhere, there's a reef (fish)!