DIN 933 (ISO4017) Hexagonal bolts can be divided into full-threaded hexagonal bolts , DIN 933 hexagon bolts are often used in conjunction with hex nuts. the tow parts are connected into a whole by threaded connection, which is a detachable connection. the self-locking performance of the fine thread hexagonal bolt is better, and it is mostly used for parts subject to greater impact, vibration or alternating load, can also be used for fine adjustment mechanism.