School officials report a growing number of teens are bringing a new e-cigarette device called a Juul vaporizer to school. The device looks like a USB flash drive, and charges when plugged into a laptop, USA Today reports.

Juul is small enough to fit inside an enclosed hand. It comes with pods of e-liquid in sweet flavors such as mango, fruit medley and crème brulee. The devices and flavored pods can be ordered online.

U.S. Senator Chuck Schumer of New York wrote a letter to the Food and Drug Administration (FDA), asking it to reverse a recent decision to delay the regulation of e-cigarettes popular among teens, such as Juul.

“To know that New York kids are much more likely to be using these new-age e-cig devices, like Juul, is not only concerning, but it could be dangerous,” Schumer said in a statement. “Up until now, the FDA was on track to reign in e-cigs and regulate them like any other tobacco product, but this recent delay, coupled with the new numbers showing a rise in the use of gadgets like Juul, which can fool teachers and be brought to school, demands the FDA smoke out dangerous e-cigs and their mystery chemicals before more New York kids get hooked.”