To activate your Acrylic LED Beach Sandal Necklace, plug in the magnetic end & push. To turn off, flip the magnetic end around & plug in the opposite side. When turned off, plastic sandal is crystal clear. Sold in packs of 25. Dimensions: Height 1.06 in. / 2.69 cm. Width 2.31 in. / 5.86 cm. Necklace 14 in. / 35.56 cm. LED Colors: 1 Blue Necklace comes ready to use with non-replaceable batteries.