Hex Counter Sunk Plug,Air Pipe Fitting 1/4" G Male Pipe Adapter 18pcs - Silver Tone - 1/8" G 5pcs
$10.53
Thread Size: G1/4(Approx OD 13.2mm); Thread Length: 8mm/0.31"; Internal Hex Width: 6mm/0.24". Material: Iron for corrosion resistance, ductility at high temperatures, and low magnetic permeability.