What are those funny-looking soft caps on NFL helmets during camp?, Sports
Guardian Caps Guardian Sports
Guardian Cap - Soft-Shell Helmet Cover for Football and Lacrosse - Reduces Impact and Protects Helmets - One Size Fits All for Youth, High School, and College Programs - Firefly Buys
Guardian Cap Debuts at Training Camps League-wide
Guardian Cap Debuts at Training Camps League-wide
Staples football pioneers use of 'Guardian Caps'
Football Guardian Cap draws mixed reviews from players, experts for safety effectiveness - The Daily Tar Heel
Arizona Cardinals defensive end J.J. Watt not fan of the new league-mandated Guardian Caps on helmets
Puffy, spongy Guardian Caps could help curb NFL head injuries - The Washington Post
Guardian Caps - Are the soft-shelled football helmet covers effective at limiting head injuries? - ESPN
Padded helmet cover shows little protection for football players - Scope
As NFL mandates Guardian caps in practice, area high school football teams have been using them for years, Sports
What are Guardian Caps and how are they helping football teams?