Guardian Cap debuts during minicamps in effort to reduce avoidable head contact
Guardian Caps: Why some NFL players are wearing them in training camps
NFL makes Guardian Caps mandatory for many positions through second preseason game - NBC Sports
NFL's use of Guardian padded helmet caps in camp draws support and skepticism - The Athletic
More padding the issue of concussions and better helmets
NYSportsJournalism.com - NFL Guardian (Caps) Of The Preseason Galaxy - Safety Impact: NFL Expands Presence As Guardian (Caps) Of The Preseason Galaxy
Funky-Looking Guardian Caps Rejected by NFL for Regulation Play, OK'd for Practice - Core77
NFL hopes to reduce head injuries with helmet experiment
Puffy, spongy Guardian Caps could help curb NFL head injuries - The Washington Post
The NFL Has Introduced 'Guardian Caps' to Reduce Concussions, and Made Them Mandatory. But Only for Some Positions. And Only Through the 2nd Preseason Game.
Guardian Caps Exceed NFL's Expectations - Guardian Sports
More padding the issue of concussions and better helmets
ProFootballTalk в X: „When it comes to reducing concussions, the Guardian Caps work well. They work so well that it's fair to wonder whether they'll eventually be used in games. /