Hot-dip galvanized stud is used for the fixing and linking function of connecting machinery. Both ends of the stud have threads, and the middle screw has thick and thin ones. It is called straight rod/shrink rod, also called double-headed screw. Generally used in mining machinery, bridges, automobiles, motorcycles, boiler steel structures, pylons, long-span steel structures and large buildings. After hot galvanizing surface treatment, antirust effect is achieved.