This type of propulsion system is particularly suited
to working vessels (tow-boats, fishing boats, river
bargers and pusher tugs) in the sea and on
rivers.
The nozzles can be of two types: "Fixed" or "Rotating"
(Steering Nozzles).

The advantages gained are the following:
- Reduction of propeller diameter;
- Reduction of propeller shaft and stern tube diameter;
- Reduction in vibrations, expecially in the wider stern as the nozzle regulates the water flow; - Reduction in ship's pitching when in rough waters;
- Increase in the propeller thrust to the tow and to the Bollard-Pull;
- Possible increase of ship speed by approx. 15%;
- Better performance from heavily loaded propellers, especially in shallow water;
- At the same conditions of speed, trawler work, Bollard-Pull, need 30% less power engine;
- The smaller engine cost, the reduction of fuel consuption, the high-performance of trasmission allow to recover the investiment within one or two years.