This is a Blue Nike Jersey that has been hand signed by Khalil Mack. This one is size XL. ?AfAE'A+aEUR(tm)AfaEUR AC/a,!a,,C/AfAE'AC/a,!A!AfaEUR|A,A,It has been certified authentic by Beckett Authentication (BAS) and comes with their sticker and matching certificate of authenticity.