Badminton is defined as 1 in the badminton competition rules of the International Badminton Federation: the ball can be natural materials, artificial materials or their mixture. As long as the flying performance of the ball is similar to that of natural feathers wrapped in sheepskin and cork ball holders. 2. The ball should have 16 feathers fixed on the ball holder. Badminton Feather 3: The length of the feather is 62-70 mm, and the length of the feather of each ball from the ball support surface to the tip of the feather should be the same. 4. Feather tips are round, with a diameter of 58-68mm. 5: Feathers should be tied with thread or other suitable materials. 6: The bottom of the ball holder is spherical with a diameter of 25-28mm. 7: The ball weighs 4.74-5.50g.. 8. Ball made of non-feathers: 8. 1: skirt made of synthetic materials or ball made of natural feathers. 8.2: The bearer is as stated in Rule 6. 8.3: The size and weight of the ball shall comply with the provisions of Rules 3, 4 and 7; However, due to the difference in specific gravity and performance between synthetic materials and natural feathers, the error cannot exceed 10%. 9: As long as the general style, speed and flight performance of the ball remain unchanged, with the approval of the relevant organizations, the standard ball may not be used in the following special circumstances. 9. 1: When the standard ball is not suitable due to the weather conditions at altitude; 9.2: Only when the change is beneficial to competition. Classification of badminton hair: high-quality badminton hair must use goose knife hair. If you use wool pieces such as duck knife hair, its quality will be difficult to guarantee. The classification of ball hair is very complicated. Because there is no unified national classification and numbering standard at present, the labels of badminton produced by various manufacturers are all customized. If different manufacturers have products with the same label, it doesn't mean that their quality is the same. Take Jinhe Factory as an example: all middle and high-grade badminton, that is, products with the word "A", are made of live plucked white goose feathers. First, it is divided into large, medium and small hairs according to the hair quality, then it is divided into one, two, three and four grades according to the hair quality, then it is divided into five standards according to the warp of the hair, and then it is classified according to the thickness of the hair stalk and the thickness of the hair. The 16 feathers used in the same badminton must be of the same category and as similar as possible. The more high-end products are used, the more consistent the 16 wig is, so as to ensure the flying quality of the products. Low-grade products, that is, the general leisure whole cork ball cover, are also made of white goose nest hair and camel hair, and their processing technology is the same as that of high-grade products, ensuring beauty and durability. 3. Add special glue to the cork slag of badminton ball head to form a ball head under high pressure. Classification: