Riddell Seattle Seahawks Flash Alternate Speed mini helmet. Hand-signed by Kenneth Walker III.The lot / autograph(s) includes an official Beckett "Rookie Year" Authentication Services serially numbered hologram for authenticity purposes. Beckett defines their "Rookie Year" authentication as "A way to acknowledge autographs obtained before an athlete starts their second full season as a professional."Authentication: Beckett "Rookie Year" Hologram