The product is a genuine BMW engine piston with con rod, suitable for various BMW models such as E81, E87, E90, and E91. Made in Germany, this high-quality piston has a diameter of 84mm and comes with piston rings included. It is specifically designed for engines with the N47N designation, such as 118d, 120d, and 318d. This replacement piston ensures optimal performance and reliability for your BMW vehicle.