Feature:It will react accordingly to your environment depending on the volume of sounds around you.Works just like the equalizer you might have seen on a stereo.EveryStyle has about four or more different levels. Depending on how loud the sounds around the shirt are,Suitable for T-shirt,Rock Concert,Bag and Car,very special! Use 2 AAA size batteries(Not included) Attention: Please do not bend or apply pressure to the flash panel;Do not submerge any part of the flash panel; Note:Clothes Excluded Card:20cm long x 14cm wide