* switch on/off button: button for play/pause function, press the button once to , and then press the button once to stop playing; motor works synchronously with music: motor rotates when playing music, motor stops rotating when music is paused. *Mode button: song switching function, a total of 12 music, each button once to play song; do not press the button music automatically play to song. *Volume selection button: these two buttons have the same function, a total of high / medium / low 3 grades of volume selection, each press the button once the volume will be cycled between the high / medium / low 3 grades to select. Arbitrary volume: The traditional baby music box has 3 levels volume only.crib mobile motor adopts stepless volume, you can choose the most appropriate volume from 0 to 100. Farewell to the traditional mobile music box. Soft music: 12 lullabys, which can be switched at will. Last one, one. Choose your baby's favorite music and go to sleep quickly. User friendly design: Automatic shutdown after 30 minutes Compatibility: Fit most crib mobile hanger,crib mobile arm.2 AA batteries are required, not included. Colour:White Material:ABS Size:14 x 9 x 3.5CM Package Contents: 1 x musicbox Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.