This "standard" size actuator is 13-3/4" long when compressed, has 2-1/2" of extension, and is suitable for the majority of trim tab installations.
Standard size actuator bodies have 4 rings at the lower end of the cylinder.
Actuators are strong nylon and fiberglass hydraulic cylinders with piston-like arms that push the trim tabs into position and hold them there (#18-23 in the diagram).
Hydraulic fluid is pumped in and out of the actuator cylinder via hydraulic tubing inside the boat which connects to a metal "through-transom" fitting that screws into a concealed connection port on the back of the upper (transom-mounted) actuator hinge — creating a "clean" appearance and eliminating hoses on the outside of the boat which could be subject to damage.
One of the unique features of the Bennett Trim Tab System is the use of concealed through-transom hydraulics.
In the rare installation where the inside of the transom is completely inaccessible at the actuator installation point, and one of Bennett's standard actuators cannot be installed, an actuator is available with external ports, so the hydraulic hoses can be routed through the transom at a location where there is no obstruction. The external line connection actuator is recommended only when necessary. See Related Products, below.
Click here for instructions for replacing an Actuator, and here for an Actuator blow-up diagram as well as examples and explanations for non-standard Actuator installations.