Seeking to reduce head contact, NFL mandates use of Guardian Cap helmet for early portion of training camp - ESPN
Youth football team first in NKY to use impact-reduction helmets to help protect athletes
Queen's Football utilizing Guardian Caps - Queen's University Athletics
Guardian Caps added to help reduce football concussions - The Witmarsum
As NFL mandates Guardian caps in practice, area high school football teams have been using them for years, Sports
Colleges add Guardian football protective helmet cap - Sports Illustrated
Guardian Caps, a soft-shell helmet cover, among CFL's new player-safety initiatives
Guardian cap' to prevent head injuries mandated for practices, CFL says
Steelers debut new, safer helmets for off-season training