Fitbit recalls more than one million smart watches over a burn risk.

Fitbit, the Google-owned maker of health tracking wearables, is voluntarily recalling its Ionic smart watch after more than 100 reports of burn injuries caused by an overheating battery, the Consumer Product Safety Commission said on Wednesday.

About one million of the devices, which track activity, heart rate and sleep, were sold in the United States from September 2017 through December 2021, with an additional 693,000 sold internationally. Fitbit received at least 174 reports of the lithium-ion battery’s overheating, leading to 118 reported injuries, including two cases of third-degree burns and four of second-degree burns, according to the commission.

Owners will be refunded $299 after returning their Ionic watch and will receive a discount code for select Fitbit devices, the commission said.

A Fitbit representative noted that the injury reports represented fewer than 0.01 percent of all Ionic watches sold, and said the recall did not affect other Fitbit products.