Product and Technical Support Resources | Vermont Gage
Understanding Class of Fit Tap Tolerance for UNC/UNCF - NEXT GENERATION TOOLING
Thread standards and tapping hole tolerances
ISO Metric Thread Tolerance Tables - Accu
KATOpedia | Pitch Diameter and Class of Fit
Everything you wanted to know about taps but were afraid to ask, styles of taps, class of thread , gh numbers , basic point in thread measurement , constants for finding pitch