Raymarine T121 Hull Transmitter for Multi-Hull Vessels

The Raymarine T121 is a wireless hull transmitter designed specifically for multi-hull sailing vessels equipped with Micronet instrument systems. This intelligent transducer provides depth and speed data from individual hulls to your Raymarine displays.

Key Features:

• Advanced Micronet wireless technology transmits data without running cables through the boat
• Automatic hull selection based on wind direction—displays automatically use data from the leeward hull
• No manual switches required for hull selection
• Ideal for catamarans and trimarans where heel angle affects sensor accuracy
• Integrates seamlessly with Raymarine ST40, ST60+, and other Micronet-compatible displays

Installation Note: Multi-hull installations require two T121 hull transmitters—one for each hull. The system uses wind direction data to intelligently select which transmitter provides the most accurate readings based on the vessel's point of sail.

This wireless solution eliminates the complexity of routing cables between hulls while ensuring your instruments always display the most reliable depth and speed information.