This is an official game-used authentic ball with a serial number, made with the NPB (Nippon Professional Baseball) 12-team unified ball and a sticker. *Unlike the blue bags used by the teams, each ball sold in shops has a serial number sticker. At NPB-sponsored autograph sessions, the autographs may be registered if they are on a ball with a sticker. When Mizuno Sports manufactures commemorative autograph balls at the request of a team, the players sign these balls, and the NPB registers and manages them, keeping track of the serial numbers. This allows for later authentication. Currently, there are no online authentication sites in Japan, so please take the ball to a Mizuno Sports shop to inquire. - Brand: Mizuno - Model: NPB Official Ball with Serial Number - Retail Price: 3100 yen - Purchase Price: 3700 yen Thank you for viewing.