Guardian Caps - Are the soft-shelled football helmet covers effective at limiting head injuries? - ESPN
NFL hopes to reduce head injuries with helmet experiment
NFL hopes to reduce head injuries with 'goofy' helmet experiment
Guardian Cap Debuts at Training Camps League-wide
NFL's use of Guardian padded helmet caps in camp draws support and skepticism - The Athletic
Bombers set to don Guardian Caps” on helmets at training camp
Guardian Cap Debuts at Training Camps League-wide
NFL, Oakley come up with face shields to protect players
NFL hopes to reduce head injuries with helmet experiment
Pittsburgh Steelers Players React to New Guardian Helmets - Sports Illustrated Pittsburgh Steelers News, Analysis and More
Chicago Bears: Why players are wearing padded helmets