Tunnel Thruster: 
Tunnel Thrusters are Fixed Pitch Propeller or controllable pitch propeller thrusters. The features as follows: 
-Superior Strength 

Tough and rational structural design has accomplished superior strength, Especially strong and durable driving shaft and seal are adopted for longer operation. 

-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 
Is especially reduced duct lip and has a structure that it is able to weld anywhere on outer surface of duct for installation, On the periodical inspection, it is almost 

Not needed to change parts except seal. 
-Various type of driving 
Compact new control system can provide easy operation. Customer can choose various configuration of prime mover, electric motor, diesel engine or hydraulic motor.