Rolling Walker Balls
From Gomerpedia
Rolling walker balls are the lesser known name for what we now refer to today as tennis balls.
History
Not many people realize that rolling walkers were created before tennis balls, and that tennis balls used to be called rolling walker balls. It was only through the popularity of tennis greats such as Roger Federer, Rafa Nadal, and Serena Williams that rolling walker balls were called tennis balls.
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