Puffy, spongy Guardian Caps could help curb NFL head injuries

NFL introduces Guardian Caps across league to limit number of brain injuries in preseason

Here's why some Patriots players are wearing caps over their helmets during training camp

NFL Makes Ruling On Players Wearing Guardian Cap During Game - The Spun: What's Trending In The Sports World Today

NFL hopes to reduce head injuries with helmet experiment

Puffy, spongy Guardian Caps could help curb NFL head injuries - The Washington Post

Guardian Caps - Are the soft-shelled football helmet covers effective at limiting head injuries? - ESPN

Guardian Cap: What are and why the NFL asks this safety measure in

Here's why some Patriots players are wearing caps over their helmets during training camp

With a little imagination NFL's new Guardian Caps take on different look in Cleveland: Crowquill