Concussions among players who wore Guardian Caps over summer
High school football teams go soft in the fight against brain injuries
Guardian Caps: NFL requires use of helmet cover at training camps
Concussions in NFL are up again after two seasons of declines
Coverage of the NFL in Guardian Caps
NFL says Guardian Caps reduced concussions by over 50
Guardian Caps — Do They Work? - The Indiana High School Football
NFL players wear Guardian Caps to reduce head trauma during
Guardian Caps: Why some NFL players are wearing them in training camps
The story behind those soft-shell puffy Guardian Caps players have
NFL CMO Dr. Sills on Guardian Caps Mandate >> Guardian Sports
This might be a dumb question, but why do they wear these extra
NFL hopes to reduce head injuries with helmet experiment