1,Rechargable Li-battery 2,Headset micrphone 3,USB/TF card ,FM Radio 4,Mini size,Easy to take 5.Reverb /Echo function V-3 Mini size big power waistband teaching tour guide speaker with Reverb/Echo Features*Mini size,easy to take*18W output power, sound can cover 800sq.m*Reverb/Echo function*MP3 by TF Card, USB flash disk supported, FM Radio Function*Built-in 2pcs 3.7V/1100mAh Lithium Battery, ...