"HOLO KROME" SOCKET PRESSURE PLUG Dryseal Socket Pressure Plugs Thread - TPI or Pitch 1/4 in - 18 NPTF Drive Size 1/4 in (hex) Length 7/16 in Drive Type Hexagon Recess Material Stainless Steel Type Plug Quantity 100 per box Thermo Forging process Unified 3A thread fit