The Coat of Arms Added Protection or False Security: Football
Guardian cap' to prevent head injuries mandated for practices, CFL
NFL hopes to reduce head injuries with helmet experiment
Large Bubble Helmets Are Guardian Caps, NFL's New Safety Measure
What are Guardian caps? See the NFL's latest head protection
NFL's use of Guardian padded helmet caps in camp draws support and
NFL introduces Guardian Caps across league to limit number of
NFL's use of Guardian padded helmet caps in camp draws support and
NFL players don Guardian Caps, designed to protect from concussion
Guardian Caps: The new helmets worn by several NFL teams