• Extremely handy for use in grinding and setting screw cutting tools
• American National or U.S. 60 Deg standards
• Very useful for finding number of threads per inch through graduations in 14ths, 20ths, 24ths and 32nds of an inch.
• Gage also has a table of double depths of threads for determining size of tap drills.
• Made of spring-tempered steel with satin chrome finish.
• Ground gaging surfaces

The Starrett C391 Center Gage features inch graduations, meets the American Unified National Standard and US 60 degree standards. American unified National Standard, 60 Deg.