Dak Prescott Signed Dallas Cowboys Authentic Flash Speed Helmet Beckett 39750 The number in the listing title is just an inventory sku for our records and is not the authentication number. The item pictured is a stock photo unless otherwise noted. This is a Dallas Cowboys full size authentic flash speed helmet that was personally autographed by Dak Prescott. Includes a certificate of authenticity from Beckett Authentication Services (BAS) and Denver Autographs.