A Sonihull transducer is screwed onto the Stern Drive Adapter so that the ultrasonic signals can be directly injected into the stern drive. A 16-18mm bolt is sued to mount the Stern Drive Adapter onto the fixed end of the stern drive leg steering ram.
Due to multitude of different metals, antifouling stern drives have always been difficult. The moving parts, soft bellows, and conventional copper antifouling paints have not been an option. A Sonihull system with a Stern Drive Adapter solves this problem easily.
Another area that has been difficult to provide antifouling to is the SailDrive. Here again the Stern Drive Adapter and Sonihull combo can not only protect your SailDrive but also protect that expensive propeller you have.
Sonihull appears to be the only viable option with results showing an impressive up to 80% in reduction in fouling.