To activate the Assorted Flashing Star Pierced Earrings simply press the button on the back of the earring. They have one light function which is a quick flash; press the button on the back to deactivate. NOTE: The LED color for the Blue Star earring is Blue, LED for the Pink Star Earring is Red and the White LED Star Earring has a White LED. This item is sold in pairs, buying 1 piece means you are buying 1 pair. Example: Order 12 pieces to receive 12 pairs. Dimensions: Height: 1.18 in. , 2.99 cm. Width: 1.18 in. , 2.99 cm.