These two pictures are of two different compressors, the one with the 4 bolt mounts and a sensor on the back is for the W124 chassis E300D (OM606)

The other one which has only 3 mounting bolts is for the 1996 and ahead E300D which are the W210 chassis.

Whilst both engines are the same, the compressor for the AC are different. Make sure which one do you have.

Attached Thumbnails

   

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)