This is a White Nike Boston Red Sox Jersey that has been hand signed by Pedro Martinez. This jersey is Size XL 2004 WS Patch. 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 tamper-proof sticker with a physical certificate. A certificate can be printed on Beckett's website for the matching authentication number.