Texila International Journal
The complete technical tables, which list exact millimeter dimensions for every thread size (M3, M10, etc.), are found in the official DIN 76-1 PDF available through DIN's official website or authorized resellers like specific dimensions
If you have a drawing or a requirement citing "DIN 76-a," it is asking for the of the undercut calculated according to the DIN 76 standard. din 76-a pdf
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