Colleges add Guardian football protective helmet cap - Sports Illustrated
Chicago Bears: Why players are wearing padded helmets
Guardian Cap: What are and why the NFL asks this safety measure in helmets | Marca
Some Broncos Linemen Appear At Training Camp With Unusual Extra Padding On Outside Of Helmets - CBS Colorado
NFL hopes to reduce head injuries with helmet experiment
Guardian Caps: Why some NFL players are wearing them in training camps
Why Alabama football players are wearing padded helmets in practice - al.com
Why are NFL players wearing padding on helmets at training camp?
Large Bubble Helmets Are Guardian Caps, NFL's New Safety Measure
Puffy, spongy Guardian Caps could help curb NFL head injuries - The Washington Post
NFL's use of Guardian padded helmet caps in camp draws support and skepticism - The Athletic
Guardian Caps - Are the soft-shelled football helmet covers effective at limiting head injuries? - ESPN
Guardian Caps | Guardian Sports
What Pros Wear: Top 5 Helmets Rated by the NFL & NFLPA - What Pros Wear
Guardian Caps: NFL requires use of helmet cover at training camps to reduce head injuries
Concussions are a huge issue in football. Outer-padded helmets could go a long way toward solving it. - ESPN
Colleges add Guardian football protective helmet cap - Sports Illustrated
More padding the issue of concussions and better helmets
How to fix the hitting problem of the NFL - Page 2
The Extra Yard: The Ins and Outs of an American Football Helmet - Stories - volumegraphics.com
Guardian Cap debuts during minicamps in effort to reduce avoidable head contact
Vikings Introduce Soft-Padded Helmets for Parts of OTA Practices
