After conducting a search, I found that "DIN 76-1 PDF" likely refers to a German standard (DIN) related to thread run-outs and run-in lengths for threaded parts.
You can purchase the DIN 76-1 standard as a PDF document from the German standardization body, DIN Deutsches Institut für Normung e.V., or from other authorized distributors. din 76-1 pdf
Would you like more information or clarification on any specific aspect related to DIN 76-1? After conducting a search, I found that "DIN