Germ Killing Vapors Enclosed inside each steripod toothbrush sanitizer is a laboratory formulated thymol compound. The compound is encapsulated in plastic with small holes that allow the thymol vapors to escape and surround your brush bristles. It’s the vapors that do all the work - see our research page for the test results if you like. The entire steripod is shipped sealed in a medical quality enclosure – ensuring that the compound is not activated [by air flow] before you unwrap. All you have to do is clip the steripod on your brush! - no batteries, no socket, no hassle! Simply Clip it on and you’re done! The steripod is ready to use out of the package - no batteries, no socket, no hassle - simply clip it on your electric or manual toothbrush and you’re done! Dont Forget! Replace your steripod and your toothbrush every three months...