Guardian Caps: The new helmets worn by several NFL teams
Guardian Cap debuts during minicamps in effort to reduce avoidable head contact
Guardian Caps: NFL requires use of helmet cover at training camps to reduce head injuries
What is the Q Collar, the device NFL players are wearing around their necks
Large Bubble Helmets Are Guardian Caps, NFL's New Safety Measure
NFL training camps: Guardian Cap players are wearing over helmets, why
Guardian Cap Debuts at Training Camps League-wide
Equipment To Protect Your Top Commodity - Training & Conditioning
FOOTBALL: NFL following Sequim's lead with protective caps
The Quest for a Better Football Helmet