Use a center gage, or center gauge, from Grainger as a useful guide for grinding and setting thread-cutting tools with a grinder or lathe. Help find the number of threads per inch through graduations of 14ths, 20ths, 24ths and 32nds of an inch. Center gages help meet American Standard or U.S. 60 Degrees . Choose the center gage from Grainger that will meet your application.