The threads on the external hexagonal screws are generally fine-threaded ordinary threads, and the round-threaded ordinary hexagonal external hexagonal screws have good self-pinning properties, and are mainly used for thin-walled parts or occasions subject to impact, vibration or alternating loads. Generally, external hexagonal screws are partially threaded, and full-threaded external hexagonal screws are mainly used for external hexagonal diameters with short nominal lengths and occasions that require longer threads. Hexagonal screws with holes are used in occasions that require external hexagonal screws to lock. In fact, there are many kinds of external hexagonal screws, such as external hexagonal screws, or external hexagonal bolts. It all means the same thing. It's just that the personal name is different.
