This story originally appeared on Quartz.

Nestle USA is recalling more than 440,000 Starbucks-branded mugs after customers reported being burned and cut after using the metallic products, the Consumer Product Safety Commission said.

The agency said Thursday that if the mugs are microwaved or filled with an extremely hot liquid, they can overheat or break, possibly resulting in burns or lacerations.

The recall, which includes four gift sets of metallic coated ceramic mugs that bare the Starbucks logo, were sold during the coffee maker’s 2023 holiday season, the agency said.

“There have been 12 incidents of the mugs overheating or breaking resulting in 10 injuries,” CPSC said. Of those injuries, nine included severe burns and/or blisters on a customer’s fingers or hands.

In one incident, the agency said, an individual “required medical attention.”

What’s the remedy?

A refund.

But first, CPSC said customers should immediately stop using the recalled mugs. The agency also suggests making a return or contacting Nestle USA for a full cash or gift card refund.