Guardian Caps - Are the soft-shelled football helmet covers effective at limiting head injuries? - ESPN
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First QB helmet designed to help reduce concussions approved
Helmet Laboratory Testing Performance Results
Steelers QB Kenny Pickett turning to new helmet technology to help avoid further concussions in 2023, National Sports
NFL enters next era of helmet safety with advent of quarterback-specific helmet, Sports
What Pros Wear: Top 5 Helmets Rated by the NFL & NFLPA - What Pros Wear
NFL enters next era of helmet safety with advent of quarterback-specific helmet, Sports
NFL 2017 Health & Safety Report
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