Sports equipment maker Defend Your Head files for bankruptcy - Philadelphia Business Journal
Miami Dolphins QB Tua Tagovailoa trying new helmet to combat concussions
What Pros Wear: What Do NFL Offensive Lineman Wear? Here's the Helmets, Cleats and Gloves Worn by NFL Starting OL in 2021 - What Pros Wear
New helmet design can deal with sports' twists and turns
NFL hopes to reduce head injuries with helmet experiment
New helmet design can deal with sports' twists and turns
NFL announces more steps to reduce head injuries
NFL Enters Next Era of Helmet Safety with Quarterback-Specific Helmet
Finally: First QB Helmet Designed To Reduce Concussions Has Been Approved by NFL
NFL & NFLPA approve first position-specific helmet for linemen – New York Daily News
First QB helmet designed to help reduce concussions approved
Football helmets are creating more problems than they solve
NFL approves QB-Specific helmet to help quarterbacks keep their heads in game - Hindustan Times