1/2 " npt thread with recessed allan head. 1/2" npt has a nominal o.d. f 0.840 grade 6061t6 aluminum. Purple anodized aluminum.
1/8" NPT Pipe Plugs Aluminum w/ allan head 12 per pkg Red anodized aluminum
1/8" NPT Pipe Plugs Aluminum w/ allan head 12 per pkg Blue anodized aluminum
1/4" NPT Pipe Plugs w/recessed allan head 12 per pkg Red anodized aluminum
1/4" NPT Pipe Plugs Aluminum w/ allan head 12 per pkg Gold anodized aluminum
1/4" NPT Pipe Plugs w/ recessed allan head 12 per pkg Black anodized aluminum
1/8" NPT Pipe Plugs Aluminum w/ allan head 12 per pkg Silver anodized aluminum
