To activate your Light Up Beach Ball, unscrew the top over battery house, remove pull tab, press button and secure that top back on nice and TIGHT to keep water out. NOTE: Water resistant Beach Balls float on water. Do not submerge. Remove from water after your fun & dry off to prevent water spots on shell. Dimensions: 11″ Diameter LED Colors: Red, Blue & Jade, creates neat rainbow color change effect. Comes ready to use with 3 replaceable AG13 Batteries.