NFL to test new position-specific helmet designed for pros - The Boston Globe
NFL to test new position-specific helmet designed for linemen
How Helmets Have Evolved to Prevent Football Concussions - Chester County Hospital
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How New Helmet Technology Will Make the NFL and NHL Safer, News, Scores, Highlights, Stats, and Rumors
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NFL to test new position-specific helmet designed for pros
We Can Make Football Safer - Scientific American
More padding the issue of concussions and better helmets