This piston rings set is designed for vehicles with N46B20B, N46B20C, N46B20E, N46B20BD, N46B20CC, and N46B20CD engine configurations.Compatible models include E60, E81, E83, E84, E85, E87, E90, E91, E92, 118i, 120i, 320i, 520i, X1, X3, and Z4.The set features a cylinder bore size of 84mm for precise fitment.Ring thickness specifications: first ring 1.2mm, second ring 1.5mm, third ring 2.0mm, supporting effective cylinder sealing.Package includes 4 pistons and 4 ring sets for a complete cylinder replacement.Designed as a direct-fit replacement to help maintain engine performance.Supplied in neutral packaging.