The story behind those soft-shell puffy Guardian Caps players have been wearing
Cowboys seen wearing protective, NFL mandated Guardian Caps at OTAs
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Puffy, spongy Guardian Caps could help curb NFL head injuries - The Washington Post
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The story behind those soft-shell puffy Guardian Caps players have been wearing
If a player wanted to wear a Guardian Cap during a game, the league would prohibit it - NBC Sports
Guardian Caps Guardian Sports
NFL hopes to reduce head injuries with helmet experiment
Large Bubble Helmets Are Guardian Caps, NFL's New Safety Measure
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NFL hopes to reduce head injuries with helmet experiment
NFL hopes to reduce head injuries with helmet experiment