Principle:No heat, flame and sparks, no battery required Advantage: Non-toxic, non-flammable, non-radioactive, wat Erproof ... .5/27*25*9.5PrincipleNo heat, flame and sparks, no battery requiredAdvantageNon-toxic, non-flammable, non-radioactive, wat erproof, windproof Usageconcert ... , nightclubs FY exhibition hall decorate/glow in the night sticks /factory direct party supplies