Simply put, the function of the spring washer is to prevent the metal of the spring from directly contacting the Rubik's Cube and wearing it. It is also said that the function of the spring washer is to limit the spring force. So, what is the function of the spring washer? 1. The function of the spring washer is realized by its elasticity and the friction of the oblique mouth. 2. Widely used in frequently disassembled joints to prevent loosening of fasteners. 3. The inner tooth elastic washer and the outer tooth elastic washer have many sharp elastic warping teeth on the circumference, which can be pressed against the supporting surface and can prevent the loosening of the fastener. 4. The inner tooth elastic washer is used under the screw head with smaller head size; the outer tooth elastic washer is mostly used under the bolt head and the nut. 5. The elastic washer with teeth is smaller than the ordinary spring washer, and the fasteners are evenly stressed and reliable to prevent loosening, but they are not suitable for frequent disassembly.