This is an Official M.L.B Baseball that has been hand signed by Chuck Knoblauch. This item was inscribed "91 AL ROY." This item has been witnessed and certified authentic by Beckett Authentication (BAS) and comes with their tamper-proof witness sticker. Beckett Authentication has recently changed their physical certificate card policy where they no longer match their serial numbered hologram with a physical certificate. A certificate can be printed on Beckett's website for the matching authentication number.