GOCHANGE Screw Thread Pitch Cutting Gauge Tool Set, Centre Gage 50 Degree Inch System and 60 Degree Metric System, 4 Pcs THE THREAD PITCH GAUGE: The thread Pitch Gauge used to measure the pitch of the thread, It sets 4pcs centre gage 55 Inch System & 60 Metric System FIT FOR: Center Gage use to grind and position thread cutting tool on a lathe. Typically used to check the thread size determination is correct MATERIAL: All 52 pcs was made by stainless steel, not easy to rust. Ensure the accuracy of measurement. CONTAIN: Metric total of 24 tablets, according to the number of pitches per piece, said pitch 0.25-6mm. Inch total of 28 tablets, each in accordance with the number of teeth per inch to represent the number of teeth 4-62. UNBEATABLE SATISFACTION: GOCHANGE products are backed by an unmatched reliability and consistency, coming with quality assurance you can trust. If you meet any problems, just don't hesitate to contact us.