This part is listed by BMW as BMW part number 72111929419 (72-11-1-929-419) and is described as Genuine BMW Slide Rail for Left Front Seatbelt on E30 3-Series 2-Door Coupe models.
Replaces obsolete BMW part number 72111888007 (72-11-1-888-007).
BMW Fitments:
3 Series
E30 (84-91) > 318i
E30 (84-91) > 318is
E30 (84-91) > 325e
E30 (84-91) > 325es
E30 (84-91) > 325i
E30 (84-91) > 325is
E30 (84-91) > 325ix
E30 (84-91) > M3
