Featured is a Ken Griffey Jr. signed Seattle Mariners Russell Athletic authentic baseball jersey. This jersey has been hand signed by Griffey and comes with the Beckett and PSA/DNA holograms and letters of authenticity. This jersey is size 48. This jersey would make a great addition to any sports memorabilia collection.. SPECIFICATIONS Autographed By: Ken Griffey Jr. Team: Seattle Mariners Sport: Baseball Authentication: PSA/DNA Authentication Services