Raymarine P79, 600w In-Hull f/ST60 [E26001-PZ]P79 In hull Our P79 in hull transducer easily adjusts to hull deadrise angles up to 22. This ensures that the beam is vertically oriented to receive echos resulting in accurate depth readings. Unlike traditional "puck" type transducers, our P79 consists of a base that is bonded to the hull and filled with liquid. The separate transducer then attaches to the base with a twist lock. The sound waves travel more efficiently though the liquid, giving the