Humminbird XP 9 20 Puck Transducer Designed to mount to the inside of your hull and transmit the sonar signal through the hull itself Single/dual transducer with 15-foot cable and slow-cure epoxy included Compatible with many PiranhaMax, FF and Matrix series Humminbird sonar systems Hull must be of single-layer, fiberglass construction and be free of trapped air or voids Backed by manufacturer's one-year limited warranty