These engine mounts allow easy swaps of the inline six engines M103/M104 and the diesel OM603/OM606 in the W201 and w124 chasiss. They have two types of mounting holes: First is like the OEM support arms found in the 2.6 m103 powered W201s. Second is like the OEM support arms found in all the 6 cyl w124s. This allows w201 owners to mount their 6cyl 15mm back. Advantages start with the usage of a bigger cooling fan, installation of a 6cyl engine with the stock 4cyl radiator and front support. And most important a better balance which the w201 with 6 cyl lacks a lot!