IBVF Flanged Adaptors have been developed to address several problems in the marine industry - particularly, the ill-advised practice of attaching in-line ball valves directly to thru-hull fittings.
Without the structural advantage of a flanged seacock base to spread the potential forces applied, this creates a physically vulnerable situation. Installing an IBVF Adapter helps supply some of the structural stability provided by a flanged seacock, without the expense of buying an entirely new valve.

Bottom port of IBVF adaptor has straight NPS threads to mate with thru-hulls; top port has tapered NPT threads to mate with ball valves
Provides a safe and sturdy assembly when in-line valves are used as seacocks
316 stainless steel versions are available by special order