The retail giant said Friday that it has pre-ordered 15 Tesla Semis—the official name of the vehicles—for testing.

Walmart (WMT) joins a list of other big companies that have preordered the electric trucks, including J.B. Hunt Transport Services, which said it would buy an unspecified number, and Michigan-based grocery chain Meijer, which has preodered four of the vehicles.

“We have a long history of testing new technology—including alternative-fuel trucks—and we are excited to be among the first to pilot this new heavy-duty electric vehicle,” a Walmart spokesperson told Fortune in an email. “We believe we can learn how this technology performs within our supply chain, as well as how it could help us meet some of our long-term sustainability goals, such as lowering emissions.”

Walmart said that it would test five of the Tesla (TSLA) Semis in the U.S. and another 10 in Canada. Walmart declined to comment on when it plans to test the vehicles and how it plans to do so.

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“While we’ll be in the testing stage, we’re excited about the potential benefits this kind of technology offers our fleet,” the spokesperson said.

Walmart also declined to comment on the specific details about its relationship with Tesla, including whether it has paid a deposit for the preorder or whether it must still buy the trucks if the testing is unsuccessful.

Tesla CEO Elon Musk said during an unveiling of the truck on Thursday that reserving a Semi cost $5,000. Production of the truck is scheduled to start in 2019.

Musk added that the trucks would be able to travel up to 500 miles on a single battery charge when filled with cargo and driving at 65 miles per hour. The Semi is a Class 8 truck, meaning in the category of the biggest freight trucks, and contains the same motors as Tesla’s Model 3 sedan.

Like Tesla’s other vehicles, including its new $200,000 Roadster, the Tesla Semi also would come with autopilot features that would help the truck drive itself, albeit in limited ways compared to a fully autonomous car. The new Semi will be able to automatically change lanes and stay within them and adjust to traffic speeds without the help of human drivers.

CNBC first reported on Walmart’s preorders.