This Miami Dolphins FLASH Alternate Deluxe Full-Size Replica helmet was hand signed by Hall of Famer Dan Marino at a private signing. It is accompanied by a Certificate of Authenticity from SportsMemorabilia.com and JSA Witness. A tamper-evident hologram will be affixed to the item. Signed items are guaranteed to pass any third-party authentication with 100% Money Back Guarantee. Each signature is witnessed by a member of our staff or comes out of a private signing.