Players not fans of guardian caps
The Coat of Arms Added Protection or False Security: Football Tests New Guardian Caps to Prevent Concussions
NFL hopes to reduce head injuries with helmet experiment
New Football Helmet Covers Improve Safety
Guardian Caps, a soft-shell helmet cover, among CFL's new player-safety initiatives
Guardian Caps leave some NFL players and coaches with concerns: 'You feel like a bobblehead'
For Giants and the NFL, it's the Summer of Guardian Caps - Newsday
NFL hopes to reduce head injuries with helmet experiment
High school football teams go soft in the fight against brain injuries
NFL health and safety officials recommend expanded use of Guardian Caps in the summer, per report
Guardian Caps Guardian Sports
Puffy helmets make life safer for young athletes