The B164 Depth and Temperature Transducer operates on either 50 or 200 mhz and provides 1kw of power to penetrate deep depths. It also It is designed to fit flush with the bottom of you hull as it has a tilted element matched to your boats deadrise. Please note; this unit must be connected to a DSM300 or DSM300G sounder module to operate with you Raymarine Multifunction display. Available in either 12 degree or 20 degree models.