Pin Bolt Diameter: 24mm Pin Bolt Length: 56mm Cylinder bore: 92.9mm OEM NO.: A2780302317 Condition: This 8-piece piston rings set is designed for compatibility with a range of vehicle models from 2011 to 2019, including X166, W166, W221, W222, GL500, S500, M278, GLS500, E500, ML500 equipped with 4.6T and 4.7T engines.The set includes eight pistons and corresponding rings, providing a complete replacement solution for engine rebuilds. This is not an OEM product.Brand/model references are included solely to assist with compatibility identification.