NFL expands rule against misuse of helmet; Guardian Caps required
2011 Army Football Media Guide by Army West Point Athletics - Issuu
Steelers QB Kenny Pickett turning to new helmet technology to help
NFL exec suggests Guardian Caps worn to protect players during
NFL makes Guardian Caps mandatory for many positions through
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Funky-Looking Guardian Caps Rejected by NFL for Regulation Play
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Steelers QB Kenny Pickett turning to new helmet technology to help
2012 Army Football Media Guide by Army West Point Athletics - Issuu