Raritan MK2 Rudder Angle Indicator [MK212]MK2 Rudder Indicator w 2" RD. Analog Panel Meter, Chrome, 12v The Ruddermaster indicates at a glance how far the rudder is from a straight ahead position. As the steering wheel is turned, the sending unit communicates the angle of the rudder to the calibration box. The calibration box transmits the rudders position to the meter. The Ruddermaster can be used both as a steering aid and to monitor auto pilot systems. Raritan offers several styles of