Sierra STT3701R Trim Tab Actuator & Control Kit This Sierra Trim Tab Actuator & Control Kit includes 4.25″ standard actuators, a controller, and harness. The intuitive dial controller allows for simple, easy to use operation. Featuring built in electronics with LED position indicators for precision. Customize your control with separate pitch and roll adjustment. An auto-retract feature activates when in a situation such as shift moving to reverse to protect your gear. Kit Contains: 4.25″ Standard Actuator Dial controller Harness Interchange: Lenco 15059-001