Designed for inboard or outboard boats, the RV-312 Plastic Thru-Hull  Transducer System lets you easily identify structures and locate fish  with the life-like clarity of RealVision 3D™ sonar.
 The RV-312 system is a 4-channel, Wide Spectrum CHIRP transducer  system with DownVision™, SideVision™, high frequency CHIRP fish  targeting and RealVision 3D™ sonar inside. The transducer system has a  built-in attitude and heading reference system (AHRS) that stabilizes  the sonar imagery, automatically compensating for vessel motion. You'll  enjoy crystal-clear imagery in waves, swells, and while maneuvering. The  RV-312 system also has a built-in fast response water temperature  sensor for quick, accurate readings.
 Raymarine's RV-312 Plastic Through Hull Transducer system pack  contains a pair of RealVision 3D transducers with internal offset to  accommodate hull deadrise angles from 1° to 12°. This completely  eliminates the need for fairing blocks. The low-profile design slips  effortlessly through the water without causing drag or cavitation. The  near-flush RV-312 system works great on trailered boats too.
 The RV-312 system features rugged plastic through hull bodies  suitable for fiberglass, steel or aluminum hulls. One transducer  transmits and receives to port and downwards, the other to starboard and  downwards, ensuring a full 180° of underwater coverage even on boats  with deep keels or other underwater protrusions. Each transducer  features a 2 meter pigtail, joining y-cable and 8 meter extension cable,  resulting in an overall cable length of 10 meters (33 ft.)