Offered here is the Black and Decker Valve Seat Stone and Pilot Handbook. This is an early manual and cover s engine from the Late 1940's to 1957. It is a 31 page manual. Has specifications such as Valve Seat angle, Pilot / Guide Size and proper part number of pilot to use, Valve seat Stone size to use. Covers Passenger Cars, Trucks and Buses, Tractors, combines & road Machinery, Marine and diesel engines, aircraft engines, and motorcycles.