NEW YORK (AP) -- McDonald's has an idea for speeding up service at the drive-thru: add another window.

Under the current setup, customers place their orders, then drive up to a window where they pick up their food. The fast-food chain says it's testing a "Fast Forward Drive-Thru" that lets customers drive to a third stop if their orders aren't ready.

McDonald's spokeswoman Lisa McComb says the Fast Forward Drive-Thru will be featured in new and renovated restaurants starting next year.

The drive-thru is an important revenue generator for fast-food chains. McDonald's gets about 70% of its sales from the drive-thru, according Richard Adams, who now runs a consulting firm for franchisees.

McDonald's Corp., based in Oak Brook, Ill, has more than 14,000 locations in the U.S.

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