The Alamarin-Jet water jet propulsion unit is a high-quality propulsion unit for boats. The jet is located at the back of the boat. It receives pumped water through an intake at the bottom of the boat. The intake duct leads the water onto the impeller and the impeller raises the pressure of the water. The change in the pressure and subsequent flow velocity creates a reactive force which thrusts the boat forward. Alamarin-Jet Oy has manufactured the units since 1976 in Alahärmä, Finland.