Porsche Seat Rail Support Inner Left 911 65 73 912 65 69 901 501 961 24 SMC000846 930 (1975 1977) and 964 (1989 1994) 901 355 627 01 930 (1975 1977) and 964 (1989 1994) models Features and Benefits:Reduces the oil blow by from the crank ventilationKeeps the oil in the engine while still allowing good crank ventilationVery simple mounting sandwiches between the crankcase and ventilation the lid breather coverUsed on all Hastech race & street enginesRecommended for all aircooled Porsche 911 engines to help reduce oil consumption caused by ingestion of oil laden air into the intake caused by excess crankcase windage and blow by Porsche Seat Rail Support 912 (1965 1969)