Flat washers can relieve pressure, increase friction, seal, shock absorption, and secure. Spring washers can increase the friction between nuts and bolts, prevent bolt loosening, and improve the stability of the connection.

Automotive fasteners are tools or accessories used to connect automotive components, and they are crucial in the assembly and maintenance process of automobiles. Their main function is to ensure the safe and reliable connection of automotive components, avoid loosening or separation during driving, and thus ensure the safety of driving. According to their different uses and shapes, automotive fasteners can be classified into various types, such as bolts, nuts, screws, washers, and pins.