Researchers in Israel unveiled a reusable face mask that can clean itself. The mask plugs into a USB charger. That heats up the mask’s layer of carbon fibers to about 158 degrees, which is hot enough to kill any lingering viruses. The reusable self-cleaning mask could be a boon for healthcare workers and hospitals, as well as the environment. “You have to make it reusable and friendly, and this is our solution,” said the mask’s developer, Yair Ein-Eli.