Mugen Power 4800mAh Extended Battery for Casio G'zOne c811 4G LTE waterproof edge w/ Black Door Cover Over 2.5x duration Over 2.5 times with 4800mAh longer runtime compared with the original 1800mAh Casio battery Comes with an extended battery door cover -Super Fit the phone- Special designed to match/fit the phone's original color and finish - With Rubber band for water resistance Do Not Support NFC function 12 Months Warranty