To activate your Cruise Ship Body Light, first pull out the paper tab, then push the button on back. To deactivate, press the button again. To attach, this Body Light comes with a safety pin back. Specifications: Width: 2.0 in. Height: 1.12 in. LED Colors: Orange, Red & Blue Batteries: Includes 2 replaceable CR927 Batteries Weight: 0.02 lbs