As in the X 10 XE, the X 12 XE con rod is not a solid rod but rather a weight-optimised rod with two webs.
The X 12 XE piston is designed with a level piston head, in contrast to the recessed piston of the X 10 XE.
The mating surfaces of the cod-rods and con-rod bearing caps form an individual fit and as a result must never be interchanged.