Light Up Valve Caps attach to your car, bicycle, or motorcycle's tire valve and operate upon movement, meaning you leave behind a swirling array of color-changing madness in the wake of all others on the road! To activate, unfasten & pull apart the metallic base. Remove the white paper strip from between the batteries & the light. Re-fasten and then attach to your tire's valve. Then ride! The little light will do the rest. Color changing LEDs are motion activated! NOTE: When you order 1 pc, you are getting 1 pack (2 lights). Comes with 2 replaceable AG10 batteries.