Mustard Book Light Clip On Reading Lamp  - Black Tiny Tim Plastic Book Light with Metal Clip Measures 1.96 x 7.09 x 1.37 inches. Includes 3 x 1.5V LR41 (AGS) cell batteries Manoeuverable arm and flexible head for better direction of light on your book Push on, push off switch and clip base so you can attach the light to your book This is not a toy. Do not look directly at LED light.Cell batteries are dangerous if swallowed. If this happens, consult a doctor immediately.