The Volvo Penta D4 and D6 engines – designed exclusively for marine applications. Experience an unmatched marine torque, seamlessly transferring maximum power to propel your vessel through every speed. With enhanced power and fuel efficiency, giving you a more enjoyable experience, a more comfortable ride and greater maneuverability. Delivering all the benefits important to a boat owner: performance, reliability, durability, running costs and maintenance. https://www.volvopenta.com/marine/all-ma