Meridian Medical Technologies, makers of Mylan’s EpiPen injector, issued a nationwide, voluntary recall of EpiPen and EpiPen Jr.

According to the company, some of the devices may have a defective part that does not allow for the activation of the injector in case of allergic reaction.

“While the number of reported failures is small, EpiPen products that potentially contain a defective part are being recalled because of the potential for life-threatening risk if a severe allergic reaction goes untreated,” the company said in a statement.

The recall affects 13 lots of EpiPen and EpiPen Jr. devices distributed between Dec. 17, 2015, and July 1, 2016. Mylan will replacing any of the affected devices free of charge.

Mylan advised consumers to keep and use their current EpiPens if needed until they get a replacement. Consumers should contact Mylan at 800-796-9526 or customer.service@mylan.com with any questions.

The list of lots under recall follows:

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