Meridian Medical Technologies issued a voluntary recall for 13 lots of the Mylan EpiPen and EpiPen Jr. Auto-Injectors.

The recall stems from the potential of the devices to contain a defective part that could result in the devices’s failure to activate. The company says the number of reported failures is small, but the defective part has the potential for life-threatening risk if a severe allergic reaction goes untreated, according to a news release.

Distributed between Dec. 17, 2015 and July 1, 2016, 13 lots are affected by the U.S. recall. People with EpiPens from lots not in the recall don’t need to replace their EpiPens.

Lots affected include: 5GN767, 5GN773, 5GM631, 5GM640, 6GN215, 6GM082, 6GM072, 6GM081, 6GM088, 6GM199, 6GM091, 6GM198 and 6GM087.

The FDA is asking healthcare professionals and consumers to report adverse reactions or device malfunctions to the FDA’s MedWatch program.