This OEM BMW hollow washer (46631453997) serves as a crucial sealing ring for hydraulic lines, ensuring leak-free operation on a wide range of classic and modern BMW motorcycles and scooters. Fits: A genuine BMW hollow washer (46631453997) used as a sealing ring for brake, clutch, or oil lines on various 1978-2006 BMW K-series, R-series, F-series, and C-series models.