Thrusters give you total control of your boat when docking and departing, regardless of wind or current conditions. No reservoir to install, no leaks, and no maintenance. High intensity seal. Black box electronics protect motor. Hardened and ground spiral bevel gear for maximum efficiency and quiet power transmission. Self-resetting thermal protection on all motors. Easy plug-together switch connections. Minimum silhouette hub for smooth water flow. Includes a spline-driven, high performance, 5-blade propeller which gives equal thrust in both directions. 4.0 kW. 5.4 hp. 7-9/32" (185mm) tunnel. Bronze gearbox. 143-lb. thrust.