Brass screws are tools that use the physical and mathematical principles of the oblique circular rotation and frictional force of an object to gradually tighten the objects.  Screws are indispensable industrial necessities in daily life: such as the smallest screws used in cameras, glasses, clocks, electronics, etc .; general screws for TVs, electrical products, musical instruments, furniture, etc .; for engineering, construction, and bridges, large screws are used Screws and nuts; transportation appliances, airplanes, trams, cars, etc. are used together with large and small screws. Screws have important tasks in industry.