Tru-Flate 13-201 Coupler/Plug Set 1/4" Female NPT Coupler And 1/4" Male NPT Plug N/A Imported Plug design has been adopted by most coupler manufacturers Considered the industrial standard Identified by the 3/16 inch pilot and flat bottom V-shaped ball groove Conforms to ANSI (NFPA) T3.20.14-1990 dimensions