Materialpolyester_blend light modes: Full On, Slow Flashing, Fast Flashing, Off.Light controller takes two AA batteries (not included). Battery lasts over 12 hours. One size fits adjustable strap included.Adjustable neck length fits most sizes. Use the neck strap slider to adjust the neck length. Minimum Neck Circumference - 10 3/4 inches / Maximum Neck Circumference - 18 1/2 inches. Novelty Party Dress Decor, Easy installation. There is a clip on the back of the mini battery box, which can be clipped to the inner test of the clothes to conceal while wearing. Perfect for concerts,costume parties,talent shows,Dance Competitions,winter formal, homecoming,senior party,college parties,Electric Glow Runs,Glow Party Outfit,Fashion shows,Celebrity events, Wedding Reception Outfits for Groomsmen,fraternity parties,mardi gras, cosplay,day of the dead,independence day,gay bars, bachelor parties,halloween,new years, carnivals, music festival,rave party,prom, bars,clubs, electric glow run, led parties,costume parties,mardi gras etc.Products from NIUNIU's store