Firehouse Subs is adding Coca-Cola's Freestyle fountain machine in each of its 437 restaurants, making the Jacksonville-based chain the largest customer to sign up for the machine.

Freestyle churns out more than 120 brands, which consumers choose from a touch screen. Atlanta-based Coca-Cola says the machine can boost traffic through restaurants and boost beverage sales.

Firehouse Subs and Coca-Cola teamed up for a test of the Freestyle machine in 2009 in Atlanta. Now, it will go national. Firehouse Subs' Cherry Lime-Aid, an exclusive original recipe, is one of the offerings on the fountains. The chain is the first to have its own signature drink brand in the Freestyle machine.

More than 1,000 restaurant locations are now carrying Freestyle now. Two weeks ago, executives said the machine was on track to be in 80 markets by the end of the year.