The new Food and Drug Administration (FDA) ban on most flavored e-cigarettes contains a loophole that allows teens to use disposable devices, The New York Times reports. Teens and school administrators told the newspaper that disposable e-cigarettes are popular among teens who formerly used Juul e-cigarettes.

The FDA rule permits the sale of menthol and tobacco flavored e-cigarettes. It also allows fruit, mint and dessert flavors to continue to be sold in disposable e-cigarettes, the newspaper notes. The loophole was designed to appease vape shop owners and adults who used e-cigarettes.

Disposable e-cigarette brands include Puff Bars, blu, Posh and Stig. They are pre-charged and pre-filled. Some are made in the United States, while other are imported from China. Some of these disposable devices have a higher nicotine level than Juul.

Last month, 30 senators sent a letter to FDA Commissioner Dr. Stephen Hahn, criticizing the loophole that allows menthol-flavored cigarettes and single-use products to remain on the market.