Guardian Caps: Why some NFL players are wearing them in training camps
Guardian Caps', NFL's Most Recent Attempt At Preventing Head Injuries
Park High School football blazes safety trail with Guardian Caps
These puffy helmet caps are the next big thing in NFL player safety, National Sports
Bellmore-Merrick athletics debuts new guardian caps, Herald Community Newspapers
What's with padded helmet caps teams are wearing
Can I Wear a Hat to Play Football?
Guardian Caps may one day be worn by players in NFL games, league executive says
Brian Robinson's BIG HAT deserves all caps because it's a BIG HAT