NFL CMO Dr. Allen Sills explains importance of mandated guardian caps during training camp
Guardian Caps: Why some NFL players are wearing them in training camps
NFL exec suggests Guardian Caps worn to protect players during practices could one day debut in games
NFL says positions wearing Guardian Caps saw 52% decrease in concussions - NBC Sports
NYSportsJournalism.com - NFL Guardian (Caps) Of The Preseason Galaxy
Guardian Cap Results: “Exceeded Our Expectations”
Funky-Looking Guardian Caps Rejected by NFL for Regulation Play, OK'd for Practice - Core77
Guardian Caps Guardian Sports
Coverage of the NFL in Guardian Caps
Green Bay Packers 2023 Draft Pick Returns To Practice After Sustaining Brain Injury