1.Suitable for Promotion, 2.Store for selling. Pocket size to carry anywhere. 3.Li-ion battery mini speaker. LF-119-1 Hamberger speaker FEATURES1.Can play music by link to mobile phone,MP3,MP4,PC,IPOD and other audio devices, if you devices have 3.5mm socket. 2.Power Source:(1) DC 5V adopter(2) USB 5V Cable(connect with) from computer. Hamburger mobile mini speaker