NFL players experimenting with 'Guardian Caps' to prevent head injuries
Puffy, spongy Guardian Caps could help curb NFL head injuries - The Washington Post
NFL Mandated Guardian Caps: Controversial Change - Sports Illustrated Seattle Seahawks News, Analysis and More
NFL exec suggests Guardian Caps worn to protect players during practices could one day debut in games
NFL players experiment with 'Guardian Caps' to protect heads
High school football teams go soft in the fight against brain injuries
What is a Guardian Cap? Meet the NFL's newest safety measure
What are Guardian Caps? NFL's latest padded helmets for added safety
Guardian Caps, a soft-shell helmet cover, among CFL's new player-safety initiatives
NFL hopes to reduce head injuries with helmet experiment - Wilmington News Journal
Why the Ticats are wearing those giant helmets at practice