8pcs Pistons Rings Kit with Pins, compatible with M5 (F10/F90, 2011–2019), M6 (F06/F12/F13, 2011–2018), X5 M (E70/F85, 2008–2018), X6 M (E71/F86, 2008–2019), and equipped with S63B44A or S63B44TU 4.4L V8 twin-turbo engines.Includes part numbers 11257598207, 11257556955, and 11257574822.Cylinder bore diameter: Φ89.00 mm.Wrist pin diameter: Φ22 mm.Wrist pin length: 64 mm.Ring thickness: first ring 1.5 mm, second ring 1.5 mm, third ring 2.0 mm.Designed to restore fit and function for the specified engine applications.