Double Check Valve Assemblies | Buttweld | G 1/2 B x 1/2 in. Male National Pipe Thread (MNPT) with 1/4 in. Female National Pipe Thread (FNPT) | MIP Threaded | Spigot x FIP | Threaded MIP | Threaded | 1-1/2" x 1" | 1-1/4" x 1/4" | 1/2" x 3/8" | 1" | 2-1/2" x 1-1/2"