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AIzaSyAYiBZKx7MnpbEhh9jyipgxe19OcubqV5w
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NFL football helmet timeline
Category:
Иное
Обновлено:
21 ноя 2017
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2432
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События
Leather helmets
Plastic helmet introduced
Soft leather helmet
Face mask added
Impact resistant
Air bladders added
Full face mask added
All players required to wear a helmet
Hard leather helmets
Chin Strap Invented
NFL officially adopts plastic helmet
Single bar face mask added
Radio helmet introduced
Protective visors are introduced
Polycarbonate helmet
Single bar helmets banned
Chinstrap used to help identify head injury
About & Feedback
Соглашение
Приватность
Библиотека
FAQ
Support 24/7
Cabinet
Get premium
Donate
The service accepts bank transfer (ACH, Wire) or cards (Visa, MasterCard, etc). Processed by Stripe.
Secured with SSL
Comments