Mens DJ Sound Activated LED Light Up Rave Shirt Asian L: bust 40", shoulder 16.5", length 25.5" Asian 3XL: bust 43", shoulder 19", length 28.5" Uses 2 x AAA batteries (not included) can be turned on or off when not in use to conserve battery There is a dial marked "max" and "min", so you can control the voice Black cotton t-shirt with a sound activated illuminating panel.