Hub has the industry standard 2.00" pulley register and uses the 2.782" bolt circle for the blower pulleys. It has two .250" key ways and fits 289, 302, 351W, 351C and the 400M crankshaft.
Crank hub is for external balance engine. Counter balance is twenty eight ounces.
The hub includes a piece of timing tape but RBS can supply a degree ring if the customer desires.