Special washer with a diameter of 5 mm with a rubber seal .
Suitable for models of pumps Koshin 1 inch inlet / outlet :
SEM-25E-BAA,SE-25F-BAD,SE-25L,SEV-25L,FS-24D,SEM-25E,SEH-25L.
It is used for fastening the Flange bracket to the engine PTO flange with bolts М5х40 CS (Koshin ID 734532274).
A set of 4 is required for one pump.