Puffy, spongy Guardian Caps could help curb NFL head injuries - The Washington Post
Guardian Caps The Rundown
As NFL mandates Guardian caps in practice, area high school football teams have been using them for years, Sports
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Playing with a pillow on your head': Buffalo Bills embrace new helmet covers
DWU, Augie find unintended benefits of protective helmet cover usage - Mitchell Republic
Large Bubble Helmets Are Guardian Caps, NFL's New Safety Measure
Guardian Caps: Why some NFL players are wearing them in training camps