Rugby was originally evolved from football. Here's another story. A school is holding a football match. There was a little boy whose ball was always robbed. In despair, he ran away with it. His move spread all at once, and many students followed his example and ran with the ball like him. This method immediately inspired people and created football. Generally, the diameter of rugby is about 28 cm -30 cm, which is a common diameter length, but the diameter of rugby of different specifications is not the same. For example, the 6 th ball will be smaller than the 9 th ball, so their diameters are different. The diameter of the No.6 ball is 27 cm, 9. Children's football is small, so the diameter will be small, while adults are the opposite, so the design can meet people's different needs.