Steelers players wearing caps at training camp
NFL players wear Guardian Caps to reduce head trauma during training camp
Guardian Cap debuts during minicamps in effort to reduce avoidable head contact
Puffy, spongy Guardian Caps could help curb NFL head injuries - The Washington Post
Steelers players wearing caps at training camp
Guardian Caps leave some NFL players and coaches with concerns: 'You feel like a bobblehead'
NFL Expands Use Of Guardian Caps In 2023 - Steelers Depot
The game of football is evolving and the Steelers have to adapt - Behind the Steel Curtain
No cap: Guardian covers are out, but one Steelers lineman plans to keep wearing it
NFL executive hints that Guardian Caps could eventually be worn in games, along with position-specific helmets