... DNV,GL.LR,NK,etc., and abtained the authentication certificate of Quality System ISO9001:2000.Product FeatureHighest propulsive efficiency in all ... operating conditions,Excellent behaviour regarding cavitation,with no erosive types of cavitationLowest pressure pulse fluctuations on the hull to minimize noise ... Tunnel thrusters,Azimuth thrusters,Water jets,also Main propulsion assembly. Cap of propeller