You are buying a Used Pressure Sensor  used in early D Jetronic system application. This is very rare and difficult part to find no longer in production.
will fit the vehicles in the list below. May also have other applications.
Refer to pictures and match your numbers before you order or when in doubt please call us,
we will be more than glad to answer your questions about this and other parts for your Mercedes.

Fits 300se, 300sel

click on compatibility for your specific year and model application