The Type 2 12 volt short shaft linear drive unit is one of the most commonly used drive types for sailing vessels. Raymarine mechanical linear drives provide powerful thrust, fast hard-over times and quiet operation. Mounted below decks, the linear drive moves the rudder directly by pushing the tiller arm or a rudder quadrant.. Suitable for wheel steered boats up to 15,000 kg displacement. Works with ACU-400 and SPX 30.