NFL players don Guardian Caps, designed to protect from concussion
Seeking to reduce head contact, NFL mandates use of Guardian Cap helmet for early portion of training camp - ESPN
NFL to Expand Guardian Cap Wear in 2023 - Steelers Now
NFL training camps: Guardian Cap players are wearing over helmets, why
Arizona Cardinals defensive end J.J. Watt not fan of the new league-mandated Guardian Caps on helmets
Guardian cap' to prevent head injuries mandated for practices, CFL says
NFL mandates extra head protection for training camp
NFL CMO Dr. Allen Sills explains importance of mandated guardian caps during training camp
Guardian Caps: What Are They & How Do They Work?
NFL exec suggests Guardian Caps worn to protect players during practices could one day debut in games
NFL training camps: Guardian Cap players are wearing over helmets, why