4pcs Engine Pistons Rings Set Φ82.00mm for F20 F23 F33 F55 F56 G30 120i 220i 11258657760 11258678931 11258618503 11258638450 This 4pcs Engine Pistons Rings Set is designed for use in specific engine models, including F20, F23, F33, F55, F56, and G30 variants.Constructed from forged aluminum with a hard anodized finish, the pistons offer enhanced resistance to wear and corrosion.The set features a cylinder bore diameter of Φ82.00mm and maintains a standard compression ratio of 11:1, supporting balanced engine performance.Each piston includes a pin diameter of Φ22mm and piston ring thicknesses of 1.2mm (first ring), 1.5mm (second ring), and 2.0mm (third ring), meeting specifications.This set is compatible with OEM part numbers 11258657760, 11258678931, 11258618503, and 11258638450, and is intended as a direct replacement for select engine applications.