Dial Indicators, Micrometers, Calipers manufacturer / supplier in China, offering Regular Rotary Master Gauges with Resistance and API Spec 7-2 Thread Gauges, Wear Resistance and Corrosion Resistance API Spec 7-2 Regular Rotary 1reg Thread Gauges in Oil and Gas Industry, Drilling Stem Thread Gauge Plug and Ring Gauge for Regular Rotary Shouldered Connection Thread Gage with 60-63HRC Hardness and Calibration Certificate and so on.