The IPS system does not have shafts, struts or conventional rudders. Two Volvo Penta diesels are positioned aft in the boat, under the cockpit sole in this case, which frees up what has typically been engine-room space. The IPS units are attached directly to the engines and protrude through the hull. They are mounted to the boat bottom with huge watertight gasketed flanges. These drive units basically swivel to turn the boat, eliminating the need for rudders. The system uses the push and pull of the counter-rotating propellers of each unit to maneuver the boat.