What are those caps football players are wearing?
Football helmets are creating more problems than they solve
Improper Helmet Fit Tied to Concussion Severity in High School
Making football helmets safer to prevent concussions
Next gen hard hats give better protection against head injury
Schools, players use their heads to address issue – Boston Herald
Puffy, spongy Guardian Caps could help curb NFL head injuries
Riddell launches Axiom, latest helmet to combat concussions
Experimental Helmet Aims To Fix Football
NFL's use of Guardian padded helmet caps in camp draws support and