Bennett actuators are strong but flexible nylon/fiberglass hydraulic cylinders. The piston-like arms push tabs into position. Fluid flows through a concealed hole in the upper hinge at the top of the actuator - thus eliminating external hoses subject to damage.
A1200SRC: Actuator Assembly - Small Version for M80/M120 (w/ Rivet Clearance on Lower Hinge)
Owner's Manual (pdf)