The Metric & Inch Plug, Pin Gauge ,thread Plug Gauge , and Ring Gauges, American Plug and Ring Gauges 1) Plain Gauge Pin Gauge The Metric & Inch Plug and Ring Gauges, American Plug and Plain Gauge, for the plain limiting hole(Plug Gauge) , material : GCr15; Carbide; ZrO2, Specification:0.200 -500mm 2) Three Wire Gauge Master Gauge 3) Thread Gauge Thread Plug , Thread Ring Gauges, Petroleum Tubing ...