New helmet design can deal with sports' twists and turns
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NFL players don Guardian Caps, designed to protect from concussion
New Football Helmet Standards To Take Effect In 2018
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NFL: Concussions dropped by more than 50% among players who wore Guardian Caps during summer
Revolutionary new ZERO1 football helmet may help NFL players reduce concussions
Helmet safety: Inside the complicated equipment industry - Sports Illustrated
Safety first: Lopers to wear padded caps in practice to prevent concussions