This is a retractable speed and temperature thru-hull transducer in a plastic housing, that is designed for use with in-hull fishfinder transducers. It comes with a Y-cable that combines with the cable from the depth-only fishfinder transducer to feed depth, speed and temperature to a DSM30 or DSM300. The housing has a valve to guard against water ingress when cleaning the paddlewheel, and a blanking plug is included.
Raymarine sells this transducer as part E66071 or P120-ST800.
This '-RAY' version is for Raymarine sounders and fishfinders that use the DSM300 transducer connector. This includes the DSM30, DSM300, DSM250, L755, L760, L1250, L1260, V820 and V850. (Do not use this version for the new a, c and e Series or for the older A Series or DSM25 which take the '-RAYA' connector).
There is also a bronze version, the B120-ST800.