DIY Multi-functional Portable Waistband Amplifier Kit Special Loudspeaker With Shell And Headset Microphone For Teacher Tour GuideDescription:- This product is based on the dual channel power amplifier integrated circuit TDA2822、 with the use of BTL output、 it has the features of  high output power  、 high fidelity and    high voice clarity.- The loudspeaker shell is provided with a wiring input jack (on the side of the shell) and a microphone input jack (on the top of the shell).- Working voltage: 3-9V (3.7V for rechargeable lithium battery)- Can use a single lithium battery to supply power、 can also use an external power supply (switch through the jumper of the circuit board)、 external power supply voltage is 3-9V.- The lithium battery can be charged with an external power supply socket、 the charging voltage must be 5V DC.- In addition to the electronic training、 this kit is also a good partner of teachers and tour guidesNote:Lithium battery is not included.Package included:1 x Amplifier Kit (including circuit board、 shell、 headset microphone、 audio cable)