These steady lights are really great. They can even help you meditate! They're subtle and cool, not bold or brash. They chill like you do, they just don't flash. To activate, twist backing clockwise until tight. To deactivate, twist backing counterclockwise. - This piece attaches with the use of a clip. - To attach, simply clip the piece in desired location. Height: 0.62 in. , 1.57 cm. - Width: 0.62 in. , 1.57 cm. - LED Colors: 1 Blue - Batteries: Includes 2 replaceable CR927 batteries. - Weight: 0.01 LB