NFL teams are using a new, safer helmet — the Vicis Zero1
Doug Baldwin: No reason for NFL players not to wear safer helmets
Football's Next Frontier: The Battle Over Big Data - Sports Illustrated
The story behind those soft-shell puffy Guardian Caps players have been wearing
Players Just Wore This Startup's New Soft Helmets in an NFL Preseason Game
High-tech football helmet maker Vicis is running out of money in sudden downfall for Seattle startup – GeekWire
How Notre Dame hopes to help a helmet revolution
The story behind those soft-shell puffy Guardian Caps players have been wearing
Despite Risks, N.F.L. Leaves Helmet Choices in Players' Hands - The New York Times
Why are NFL players wearing padding on helmets at training camp?
NFL exec suggests Guardian Caps worn to protect players during practices could one day debut in games