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Firestone Patented Gum-Dipping Process

By this process every cotton fiber in every cord in every ply in every Firestone Tire is saturated and coated with pure rubber--eight additional pounds of it are absorbed in every one hundred pounds of cord--eliminating damaging frictional heat, the greatest enemy of tire life. No other tire has such blowout protection, because no other tire is built nor can be built with Gum-Dipped High Stretch Cords.

 In Akron rubber workers were known as gummers, and managers were sometimes said to be gum-dipped. The term came from the process of dipping strips of cloth in rubber until they were completely coated and uniform, and then adding the strips to tread for greater strength and flexibility. In the early years Firestone Gum-Dipped tires were the deluxe line—the very best.