Concussions among players who wore Guardian Caps over summer dropped more than 50%, NFL says - ESPN
Could Guardian Caps be used during NFL games for player safety?, Pro Football Talk
Coverage of the NFL in Guardian Caps
NFL says positions wearing Guardian Caps saw 52% decrease in concussions - NBC Sports
Funky-Looking Guardian Caps Rejected by NFL for Regulation Play, OK'd for Practice - Core77
NFL players wear Guardian Caps to reduce head trauma during training camp
Could Guardian Caps be used during NFL games for player safety?, Pro Football Talk
NFL exec suggests Guardian Caps worn to protect players during practices could one day debut in games
Guardian Caps: NFL requires use of helmet cover at training camps to reduce head injuries : r/nfl
NFL Mandate of Guardian Caps - 2023 Season >> Guardian Sports