This is a White Nike Boston Red Sox Jersey that has been hand signed by Pedro Martinez. This jersey is Size L 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.