Digital Voice Amplifier, DinoFire Voice Amplifier for Teacher (Function Speaker, Recorder, FM Radio, MP3 Playing) with Comfortable Wired Microphone Headset Waistband and Belt Clip MULTI-FUNTION: Voice Amplification + Record Mode + FM Radio Mode+ Aux Mode+ MP3 Player Mode support TF card and U disk RECHARGEABLE and LONG USING TIME: rechargeable voice amplifier with built-in 2500mAh Lithium rechargeable battery supports using time above 12 hours after a full charge SOLID BUILD and PORTABLE: solid build quality material ABS very smooth and comfortable; size is 3.4x4.7x1.8inch, which is very portable to use LOUD and CLEAR: use the Voice Amplifier to make your sound very loud and clear and protect your vocal cord NOTE: Press M button to switch modes; Keep a distance between the microphone and the speaker when you adjust the microphone