Guardian Cap: What are and why the NFL asks this safety measure in helmets
LOOK: All 30 NBA team logos have been re-created as NFL helmets
EXPLAINER: NFL using helmet caps for player safety, research
Helmets don't eliminate concussions. It's time for the NFL to ditch them, NFL
Inside Slant: Re-imagining NFL helmets - ESPN - NFL Nation- ESPN
Combining NFL helmets with local NBA, MLB, NHL teams' colors
NFL hopes to reduce head injuries with 'goofy' helmet experiment
Montrose football players wearing new plastic shields to try and prevent spread of COVID-19
NFL Partners with Oakley to Develop Innovative Mouth Shield Technology