SCHWARTZ SPORTS MEMORABILIA, INC. Is the EXCLUSIVE AUTOGRAPH Agent for NFL Hall of Famer Barry Sanders, and conducts hundreds of public and private signings each year with athletes all across the country. Please check out our website for more information. (Please note image of item is a stock photo image, as we have multiples of the item in-stock). Dan Marino Signed Miami Dolphins FLASH Riddell Speed Mini Helmet -(SCHWARTZ COA). Dan Marino signed Miami Dolphins Flash Riddell speed mini helmet. Item comes with a Schwartz Sports Memorabilia tamper-proof numbered hologram and Certificate of Authenticity which can be verified online.