This part is listed by BMW as BMW part number 32411094811 and is described as Return Pipe for 1988+ E30 318i/325e/325i models (including 318ic and 325ic convertible).
BMW has two hoses they call a Return Line - this is the hose running from the power steering cooler to the reservoir. It returns fluid back to the reservoir. Like the Inlet/Supply Hose it has non-reusable crimped hose clamps where the hose meets the reservoir. Leaks are very common here as the clamps loosen and the rubber hose swells.
Fitment Note: This PS return line / hose is only for the E30 models built 10/1987 (October of 1987) or later. Models before the 1988 model year use a different early style PS return hose, while the 1988, 1989, 1990, or 1991 E30 3 Series (as well as 1992/1993 E30 convertible models) use this later style hose / line / pipe.
This is an OEM E30 PS hose manufactured by Cohline - the original supplier to BMW for this part, as well as many other components. As the OEM it meets all of BMW's original design, fitment, and performance requirements and is TUV approved. OEM parts are the best alternative to more expensive Original BMW parts because they are virtually identical without the inflated price tag. This part has a two year warranty.
BMW Fitments:
3 Series
E30 (84-91) > 318i
E30 (84-91) > 318is
E30 (84-91) > 325e
E30 (84-91) > 325i
E30 (84-91) > 325is