Football helmet - Wikipedia
Guardian Caps - Are the soft-shelled football helmet covers effective at limiting head injuries? - ESPN
Best New Gear and Coolest Gadgets This Week, According to Men's Journal - Men's Journal
Daily Slop - 22 Aug 23: Ravens are now the most recent NFL team to lose a preseason game; Washington at 2-0
What Are the Experts Saying About Guardian Caps – The Concussion Blog
FNF Coaches 2019 Player Safety by A.E. Engine - Issuu
Philadelphia Eagles: Jason Kelce has hilarious response to new safety measures
Ask the Old Guy Mailbag: Who makes the 53-man roster and who is on the bubble
Guardian Caps - Are the soft-shelled football helmet covers effective at limiting head injuries? - ESPN
The Lass Word: This Year's Preseason Games Are Actually Important
Puffy, spongy Guardian Caps could help curb NFL head injuries - The Washington Post
Shell game: Player safety looming concern as new season approaches, Local Sports
Why Alabama football players are wearing padded helmets in practice