Smith] NFL says positions wearing Guardian Caps saw 52% decrease in concussions : r/nfl
Large Bubble Helmets Are Guardian Caps, NFL's New Safety Measure
Coverage of the NFL in Guardian Caps
What are Guardian Caps? Shadow Hills football using new device to reduce head injuries
Smith] NFL says positions wearing Guardian Caps saw 52% decrease in concussions : r/nfl
Concussions in NFL are up again after two seasons of declines - The Washington Post
NFL Releases Concussion Data After Use of 'Guardian Caps' During Offseason - Sports Illustrated
Why Alabama football players are wearing padded helmets in practice
NFL report: concussions dropped 50 PERCENT when players wore new 'Guardian Caps' over the summer
Guardian Caps - Are the soft-shelled football helmet covers effective at limiting head injuries? - ESPN
NFL's use of Guardian padded helmet caps in camp draws support and skepticism - The Athletic
High school football teams go soft in the fight against brain injuries