EXPLAINER: NFL using helmet caps for player safety, research
The story behind those soft-shell puffy Guardian Caps players have been wearing
Guardian Caps NFL: What player positions are required to wear them?
Guardian Caps - Are the soft-shelled football helmet covers effective at limiting head injuries? - ESPN
NFL CMO Dr. Allen Sills explains importance of mandated guardian caps during training camp
Dallas Cowboys Practice Squad Updates: Who Returned and Who Didn't?
Annotating Newsela articles to develop deep reading skills – Learning Aloud
Here's why some Patriots players are wearing caps over their helmets during training camp
The story behind those soft-shell puffy Guardian Caps players have been wearing