NFL CMO Dr. Allen Sills calls kickoff rule 'stopgap' measure, talks future of playing surfaces, Guardian Caps
Padded helmet cover shows little protection for football players - Scope
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Guardian cap' to prevent head injuries mandated for practices, CFL says
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As NFL mandates Guardian caps in practice, area high school football teams have been using them for years, Sports
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Guardian cap' to prevent head injuries mandated for practices, CFL says
More Guardian Caps, And '0' On The Field