Flathead Ford V-8 cast iron cylinder head, used, stock. No casting number but has "Made in USA" and FOFB, and 6-15-41. 40 6050-B. Small spark plug wells.  Hot tanked, Magnetic particle checked.  No cracks found.  For flat top pistons, 18 mm spark plugs. Freshly resurfaced.  This Left or Driver Side head.  Combustion Chamber capacity 71.5 cc.