Are you trying to decide between and Type B (short) for a tight assembly?
When incorporating DIN 76-A into your CAD models or technical drawings, keep these best practices in mind: 1. Strength vs. Clearance din 76-a pdf
DIN 76-1 defines the shapes and dimensions of thread undercuts. The "Type A" designation specifically refers to the standard undercut for external metric threads. Why Use an Undercut? Are you trying to decide between and Type
It provides a "run-out" area for the thread-cutting tool. din 76-a pdf
It allows the bolt head or nut to sit flush against the workpiece.