BPS Marine BPS-4 4-Transducer Ultrasonic Antifouling System - 12VDC [BPS-4]BPS 4 4 Transducer Ultrasonic Antifouling System 12VDC The BPS 4 is a four transducer system that can add antifouling protection to hulls, drives, rudders, stabilizers, and more. This single system can provide ultrasonic antifouling protection for hulls up to 50ft in length or can be combined with additional systems for larger vessels. The BPS 4 can also be tasked with protecting drives and rudders. The BPS 4 Package Includes: 1x BPS 4 Control Module