The popular 9-Plus Hot Rod Housing is similar to the early style 9-inch Ford stock housing, which is now nearly extinct. The 9-Plus model is made of premium grade forming steel with a slightly thicker gauge of steel for increased strength and rigidity. The ends are precision machined to accept a 3-inch O.D. x .188" wall tube. A machined chamber is supplied on each end of the Hot Rod housing to provide a good weld joint. This style of housing is very popular for street rods, or other space limited vehicles, due to the fact that the shape of the housing provides increased clearance for mounting brackets and the routing of exhaust pipes.