Amazon customers in major urban centers have a new option for returning unwanted merchandise: metal lockers.

For several years now Amazon’s customers have been able to receive their orders in these lockers, receiving a code to unlock their locker when a package is delivered.

Now, customers can do the same thing in reverse. Once they indicate that they wish to return a product, Amazon will send the customer a code to unlock an empty locker and leave the unwanted merchandise.

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In an industry where the return rate can be as high as one-third, the new service is aimed at reducing return shipping costs by creating a central pickup location that UPS drivers will already be visiting, The Wall Street Journal reports.

The lockers, located in places like garages and grocery stores in cities such as New York, Seattle and London, have helped customers securely receive packages while out of town or at work since the program launched in September 2011.

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Amazon spent $8.59 billion to fulfill orders in 2013, the Journal reports, and has been on a construction spree, building fulfillment centers close to major metropolitan areas to reduce delivery wait times.

Amazon will charge customers the same amount to use the new locker return service as it does for returns dropped off at UPS locations. Packages must be no larger than one cubic foot.

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