Butterfly nuts are a type of nut with a unique shape. The protruding arc at the head resembles a beautiful butterfly. Butterfly nuts not only have a high level of appearance, but also have significant functional applications.

Generally speaking, butterfly nuts can be classified into cold heading butterfly nuts, cast butterfly nuts and pressed butterfly nuts according to their different processing techniques. According to their shapes, they can be divided into two basic shapes: square-fin butterfly nuts and round-fin butterfly nuts.