... the outside sound (Loud or Light and different music beats will flash different effect ),the product has ... or back . can be used on the Bar ,Disco,Dance Ball ,Sports Show , Ballcourt,Concert ,and other Lively ... parties ,it can flash with the music or sound . can enrich the Lively mood and ... fans and the companies wnat to advertise.when the music ring ,the pattern on the T-shirt flash, ...