A new way to scrub your bottle - just drop these in and shake it clean! 3 premium, multi-density, toothbrush grade bristle balls in 3 sizes fit even narrow mouth bottles. Scrub hard to reach surfaces with a quick shake. Super efficient, hygienic, kinetic foaming action coats all surfaces killing bacteria. Dry rack and travel/carry case included. Environmentally friendly, just one drop of soap is enough for most containers.