RBS carries a full supply of XRP fittings that can help the racer when plumbing there hot rod. From time to time there will be an application where a racer will need to adapt. something form a larger pipe thread to a smaller pipe thread and with these anodized alum. reducers these are just the ticket for that application.
Made from billet alum. to help keep the hot rod light and anodized for corrosion and galling protection.
The first number is the male pipe thread and the second number is the female pipe thread.