To activate your Light Up Ice Cream Cone Beaded Necklace, just press the button on back. Lights flash for 18 seconds. Want more? Press the button again. This auto-off helps kids preserve batteries. Dimensions: Beads 28 in. long Ice Cream 2.5 in. tall & 1.5 in. wide LED Colors: 1 Red, 1 Green, 1 Blue Ice Cream Cone comes ready to use with batteries, sealed for child safety. Batteries not replaceable.