To activate your Light Up Ribbon Necklace, press the button on the battery pack. Choose from three awesome light settings. When turned off, plastic charm is crystal clear. Height 2.5 in. – Width 1.25 in. – Necklace 20 in. – LED Colors: 1 Pink – Batteries: Includes 2 replaceable CR1620 batteries. – Weight: 0.03 LB