This Mitchell & Ness 1997 Seattle Mariners All Star jersey has been personally hand-signed by Ken Griffey Jr. It is officially licensed by the MLB and comes with an individually numbered, tamper-evident hologram from Beckett Authentic. To ensure authenticity, the hologram can be reviewed online. This process helps to ensure that the product purchased is authentic and eliminates any possibility of duplication or fraud. Includes tamper-evident hologram to ensure authenticity. Officially licensed. This product is guaranteed authentic and includes a Beckett Certificate of Authenticity and an accompanying tamper-evident Beckett Hologram.    Includes certificate of authenticity and hologram! The signature is guaranteed authentic through the Beckett hologram system.