O.J. Simpson signed jersey and card, both are professionally authenticated. The jersey is a size ADULT LARGE and authenticated by James Spence Authentication (the premier name in signatuer authentication. This jersey comes with the JSA (James Spence Authentication) sticker and card as proof it was signed by O.J. Simpson in sharpie silver paint pen. 
 
Additionally we have a very rare HOF inscribed card, signed by Simson and authenticated by PSA. PSA is the premier sports card grading company and they graded the card a 9, MINT, condition. The card is essentially flawless and alone sells for $450 in some places online.
 
The Jersey is basically free and you get the card, or vice-versa. Good luck, this will not last.