Guardian Caps leave some NFL players and coaches with concerns: 'You feel like a bobblehead'
NFL Mandates Guardian Caps >> Guardian Sports
National Football League (NFL) on LinkedIn: NFL.com, Official Site of the National Football League
Lee Hanson on LinkedIn: NFL Presents: League-wide Guardian Cap Use to Reduce Head Impacts
Puffy Guardian Caps Could Reduce NFL Player Concussions
NFL injuries cause for concern – The Expedition
Lee Hanson on LinkedIn: NFL Presents: League-wide Guardian Cap Use to Reduce Head Impacts
NFL Mandates Guardian Caps >> Guardian Sports
Guardian Cap debuts during minicamps in effort to reduce avoidable head contact
Guardian Cap Results: “Exceeded Our Expectations”
NFL Presents: League-wide Guardian Cap Use to Reduce Head Impacts
NFL reports reduction in concussions among players who wore Guardian Caps in preseason - The Athletic
NFL hopes to reduce head injuries with helmet experiment
Guardian Caps debut at NFL training camps around the league