The M20x65 is the "Goldilocks" size for mid-to-heavy industrial equipment. You’ll find it in:
Unlike a bolt, which twists as you tighten the head, a stud remains stationary. You apply torque to a nut on the other end, which means the stud only experiences pure tension . This results in much more accurate and even clamping across a gasket or flange. shpilka m20x65 gost 22032 76
This is the nominal diameter (20mm), a "beefy" size capable of handling significant loads in machine building. 65: The total length in millimeters. The M20x65 is the "Goldilocks" size for mid-to-heavy