Amazon shoppers have a new way to give back — using those cardboard boxes that may have piled up during the holiday gift-purchasing season.

The online retailing giant has this year teamed up with Goodwill to let customers use their empty cardboard shipping boxes, fill them with clothing, small household items and accessories that are no longer needed, and donate them.

Customer print out a free shipping label, and UPS or the U.S. Postal Service will deliver the donation box to Goodwill. The donations go to the nearest participating Goodwill location.

The program, Give Back Box, was founded by Monika Wiela, a Polish businesswoman who came to the U.S. and ran a shoe exporting business in Chicago, according to a 2014 Forbes profile.

Wiela told Forbes that Give Back Box first began working with technology retailer Newegg. It has added many other retailers, including Overstock.com, Ann Taylor, and REI. The company’s website says it’s based in Los Angeles.

The program announced its partnership with Amazon on Dec. 14.

Goodwill Industries International promoted the program in late November, at the start of the holiday shopping season, saying the Give Back Box program had launched just before Cyber Monday in November 2015.

The donations made to Goodwill with help create jobs and “transform lives” in accordance with the nonprofit’s mission, Goodwill said.

The program also diverts cardboard, which Goodwill described as the largest contributor to landfills. Since Give Back Box launched, more than 16,400 boxes have been shipped under the program, according to Goodwill.

More information is on Give Back Box’s website.