This part is listed by BMW as BMW part number 11121316705 (11 12 1 316 705) and is described as a Head Gasket in the standard 1.74mm thickness for E28 M5, E34 M5, E24 M6, and E26 M1.
This is an OEM Head Gasket for M88, S38 engines manufactured by an original supplier to BMW for many gaskets and seals. As an 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:
5 Series
E28 (82-88) > M5 (87-88)
5 Series
E34 (89-95) > M5 (91-95)
6 Series
E24 (77-89) > M6