To activate the LEDs in your Bouncy Ball, just throw it down on a hard surface. Bright lights will flash for about 18 seconds, then shut off automatically. Dimensions: Diameter 2.25 in. LED Colors: Purple Purple Bounce Balls come ready to use with non-replaceable batteries. Packaging: May purchase individually. Retail ready in a 12-piece stylized display box (Per every 12 you order). 144 balls per shipping carton.