This piston and rings set is designed for 2.1 L L4 Diesel OM651 engines found in C Class and Sprinter models.The kit includes piston rings for four cylinders.Technical specifications include a standard 0.00 size suitable for non-expanded cylinders, a cylinder bore diameter of 83.00mm, and ring thicknesses of 2.0mm for the first ring, 1.75mm for the second ring, and 2.0mm for the third ring.This product serves as a functional replacement to restore engine performance.Compatible part numbers include 6510300417, 6510300800, 6510300917, 6510301017, 6510301117, 6510301917, 6510303317, A6510300417, A6510300800, A6510300917, A6510301017, A6510301117, A6510301917, A6510302017, A6510303317, 6510300024, 6510300124, 6510300224, A6510300024, A6510300124, and A6510300224.Fits engine codes OM651.911, OM651.912, OM651.913, OM651.916, OM651.921, OM651.924, OM651.925, OM651.940, OM651.950, OM651.955, OM651.956, OM651.957, OM651.960, OM651.961, and OM651.980.Vehicle compatibility includes E250 (2014-2016), GLE300D (2016-2017), GLK250 (2013-2015), ML250 (2015 onwards), Sprinter 2500 (2014-2017), and Sprinter 3500 (2014-2017).Please verify your vehicle model and engine number before purchase to ensure proper fitment.