BXT&reg; Portable Rechargeable Super-small Buddy-jack Mode Ball Mini Speaker with Bass Resonator - For Moblie Phone, Pc, Ipod, Mp3/mp4, Laptop, Psp, and Other Digital Devices with 3.5mm Standard Audio Cables. (black) Built-in packable 3.5mm standard audio cable can be easily and conveniently connected into any multimedia device with 3.5mm port, including pc, moblie phone, psp, etc. This mini speaker is very small in size (diameter: 6cm, height: 4.4cm, weight: 83g), can be put into your pocket, very portable. Pioneering patented technology: extendable resonance of the bass box technology enables stronger effect. Embedded type lithium battery can use USB or power adapter for charge, more convenient and user-friendly. Unique buddy-jack mode, you can use several mini speakers at the same time, thus to make the sound effect more surprising.