Very early rare piece of hot rod history , Developed on the west coast by Al Sharp of Douglas & Sharp of California and intorduced around the 1950's. This specimen of vintage speed equipment is a very hard to find piece of early performance equipment. It is a very good example in its original cast condition, There are no chips, cracks, welds or repairs, All of the threads are good. You may want to replace the studs and perhaps have it media treated as it has been in a barn for many decades. This one has threaded upper ports perhaps to operate a columbia rear end? Not sure on that. It is sold as is. Local pick up or buyer pays shipping.