Rob Gronkowski Signed New England Patriots F/S Speed Helmet RAD 40402 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 New England Patriots full size speed replica helmet that was personally autographed by Rob Gronkowski. Includes a certificate of authenticity from Radtke Authentication Services (RAD) and Denver Autographs.