Guardian Caps NFL: What player positions are required to wear them?
NFL executive hints that Guardian Caps could eventually be worn in games, along with position-specific helmets
Guardian Caps: Why some NFL players are wearing them in training camps
As NFL mandates Guardian caps in practice, area high school football teams have been using them for years, Sports
EXPLAINER: NFL using helmet caps for player safety, research
NFL exec suggests Guardian Caps worn to protect players during practices could one day debut in games
NFL's top doctor does not expect Guardian Caps to be worn in games - NBC Sports
What Pros Wear: Guardian Caps What are Those Helmet Covers Being Worn in Practice? - What Pros Wear
NFL executive: Guardian Caps could one day be used in games
Puffy, spongy Guardian Caps could help curb NFL head injuries - The Washington Post
What is the NFL Guardian Cap? Will it do anything to reduce concussion? — Dr. Mark Heisig
NFL Mandated Guardian Caps: Controversial Change - Sports Illustrated Seattle Seahawks News, Analysis and More
Guardian Cap: What are and why the NFL asks this safety measure in helmets