Tunnel Thruster :

 Marine tunnel thruster

Tunnel thruster is a transversal propulsion device built into, or mounted to, either the bow or stern, of a ship or boat, to make it more maneuverable. tunnel thrusters make docking easier, since they allow the captain to turn the vessel to port or starboard side, without using the main propulsion mechanism which requires some forward motion for turning. tunnel thruster is of the same principle, fitted at the stern. Large ships might have multiple bow thrusters and stern thrusters.

-Superior Strength
tunnel thruster tough and rational structural design has accomplished superior strength

-Less Noise and vibration
employing thicker duct plate, developing new propeller design and so on have achieved less noise and vibration which follow comfortable living environment on board
-Easy Installation and Periodical Inspection