Vicis high-tech helmets take top 3 spots in NFL's annual performance ranking of equipment – GeekWire
Seattle Seahawks players talk about their experience wearing new high-tech Vicis helmet – GeekWire
NFL's use of Guardian padded helmet caps in camp draws support and skepticism - The Athletic
Urgent next step on football head injuries is a truly comprehensive database
Laboratory Evaluation of Shell Add-On Products for American Football Helmets for Professional Linemen
Laboratory Evaluation of Shell Add-On Products for American Football Helmets for Professional Linemen
Do NFL players have numbers on their helmets? If so, why? - Quora
Design and Virtual Testing of American Football Helmets–A Review
NFL to test new position-specific helmet designed for linemen - ESPN
What Pros Wear: Top 5 Best Youth Football Helmets (2020) - What Pros Wear