Seastar STT3231R Dometic STT3231R Seastar Trim Tab System, Stubby Actuatorss, Edge Mount w/Dial Controller, 12" x 12"Our intuitive dial controller is simple to adjust to get your boat on plane quickly and efficiently. A programmable favorites button makes for effortless operation. The auto retract feature ensures reliability and safety, whatever the conditions. All systems include 2 electric actuators, dial controller & harness. Turn the 2 1 4" dial and the actuators quickly level the boat Single press bow up and bow down along with auto home Intuitive dial