Fork joint with bolt

Fork joints GN 751 consist of a fork head according DIN 71752 and a pin with axial shaft safety (Type KL and SL) or a snap-on spring pin (Type B). Size d1 = 12 is supplied with a fine thread M12x1,5 according to DIN. In practice, however, M12x1,25 is preferred. Standard DIN 71752 does not foresee size d1 = 20.