Why Alabama football players are wearing padded helmets in practice
High school football teams go soft in the fight against brain injuries
Guardian Caps Guardian Sports
Guardian Caps - Are the soft-shelled football helmet covers effective at limiting head injuries? - ESPN
Guardian Caps - Are the soft-shelled football helmet covers effective at limiting head injuries? - ESPN
NFL players experimenting with 'Guardian Caps' to prevent head injuries
NFL executive hints that Guardian Caps could eventually be worn in games, along with position-specific helmets
NFL's use of Guardian padded helmet caps in camp draws support and skepticism - The Athletic
What are Guardian Caps? Shadow Hills football using new device to reduce head injuries
Why Utah players wore Guardian Caps during camp - Deseret News