The Minn Kota Transducer Mounting Kit MKR-15 allows transducer mounting on the lower unit of bow- or transom-mount trolling motors. Rugged, durable construction ensures marine-grade dependability. The Minn Kota Transducer Mounting Kit MKR-15 fits transducers of all major manufacturers with lower-unit motor sizes 3-1/4", 3-5/8", and 4-1/2".Manufacturer model #: 1840201. Allows transducer mounting on lower unit of bow- or transom-mount trolling motors Rugged, durable construction Works with transducers from all major manufacturers Fits lower-unit motor sizes