USB mini Stereo Speaker with Hook

Description:
Built-in rechargeable battery
Frequency Scope: 200Hz ~ 17KHz
Output: 89db ± 3db 
Impedance: 4Ω (ohm)
Rated at 2.7 Watt per channel
Battery capacity: 300mAh
Simple, just plug-in, no driver install
Apply to any audio devices with 3.5mm headjack, e.g. PC, Mac, iPad, iPod, iPhone ... etc.
Dimensions: 43 x 43 x 46mm (approx.)
Weight: 106g