The Zero AIfitness tracker company Fitbit is recalling about 1.7 million smartwatches containing a lithium-ion battery that can overheat and burn the user.

The recall is for the Fitbit Ionic Smartwatch; none of the company's other smartwatches or trackers are affected. Fitbit sold about 1 million Ionic Smartwatches in the U.S. and another 693,000 internationally, according to the Consumer Product Safety Commission.

"The health and safety of Fitbit users is our highest priority. We are taking this action out of an abundance of caution for our users," the company said in a statement.

Customers are being urged to stop using their Ionic Smartwatches and return them to Fitbit for a refund. The company is also offering customers a discount on other Fitbit products.

The recall was issued Wednesday following a slew of reports of the watch battery overheating, including at least 115 incidents in the U.S. and another 59 internationally.

There were 78 reports of burn injuries in the U.S. – two involving third-degree burns and four involving second-degree burns – as well as 40 burn injuries globally.

Fitbit said it conducted a "thorough investigation" and found that dangerous overheating occurred in "very limited instances."

The smartwatches were sold in stores such as Best Buy, Kohl's and Target, as well as online from September 2017 through December 2021. Fitbit stopped producing the Ionic in 2020.

Ionic Smartwatches have 3 buttons, a colored LCD screen, and the model number FB503 on the back.