Multicolour 1pc Light Up Led Earring Ear Stud Dance Party Accessories by Chonlyshop Zircon Size:app 7mm Total Length:app 2cm, Package included: 1 pc cubic zirconia LED earring (not 1 pair) Battery:LR521 button battery (replaceable) Material:Stainless steel earring with Cubic Zirconia stone Weight:About less than 1g When u wear the earring,the light is on, pull out the post of the earring slightly,the light is off. Notice: If you feel a little more shy You can even turn the LED's off (by pulling out the post slightly)