This baby music mobile is made of ABS, fit for babies under 5 year's old, which can be installed on baby's bed with arm. The toys will rotate while music playing if it is hung over the hooks. Except that you can play music tracks stored in music box with buttons directly,you can also connect the music box with your mobile phone via Bluetooth, then play music from your mobile phone as you like. Specification Music Box Dimensions(L*W*H): 3.5in*3.5in*1.38in Weight: 4.37oz Color: White Micro SD Card Capacity: 128M(12 tunes included) Power Source: 2 AA batteries(not included) Support USB Data Transmission: YES 12 tunes already preloaded, you can download anyother music or audio stories at you will via USB cable. Benefits 1.Light music helps your baby easier fall asleep 2.Music may even help strengthen premature babies 3.Music plays a crucial role in `wiring` your baby`s brain for learning. 4.Listening to music will help teach your infant about patterns and sequence, and about rhythm, beat and tone which are useful for problem-solving and reasoning. 5. Early music exposure can help promote critical listening skills, language and literacy, creativity and coordination Note Brackets/arms and toys are not included but available in the market. Package Included 1 x Baby Musical Mobile Music Box 1 x 128M Micro SD Card 1 x USB cable(for data transmission) 1 x User Manual