The Splash Brite lights up when it hits the water and shuts off when it comes out of the water. No buttons, no light sticks, no battery required. Just slip it on and fish. The Splash Brite is built with Thill's premium standards. Its sealed and contained center slip float design features a line friendly grommet and Hi-Vis top. It offers little resistance and excellent sensitivity - making it a perfect daytime float once its battery dies. Fully Automatic. Lights activate upon contact with water. No batteries required. A true center slider slider slip float. Line friendly brass grommet.