How many badminton players can you recommend?

The patent of inkstone chess is resistant to beating and moisturizing, which is effective for all kinds of balls. Baidu Academic has advantages over blisters or smoked balls:

It is more troublesome to use blisters or smoked balls. Second, it is not easy to master proper limit, and it is easy to explode. Third, it needs to be soaked again after use. This patent can completely solve the problem of bubble ball or smoke ball at one time, increase strength and greatly improve impact resistance, and will not expire within three years.