The crankshaft hub can also rotate due to the loosening of the main hub bolt. The screw lock holds the screw in position and does not allow it to loosen.

Manufacturer: AWRON
Product type: Motor parts
For: BMW M2 F87 COMPETITION, BMW M2 F87 COUPE, BMW M3 F80, BMW M4 F82, F83

S55 crankshaft central screw lock

Manufacturer AWRON