[Small But Very Powerful] — If you are looking to purchase a personal voice amplifier that is small in size and lightweight, then S17 is right up your alley. It is a portable microphone speaker with 8 watts output power, which can clearly amplify your voice and protect your vocal cords, allowing you to easily make your voice heard by 25 to 100 people. [Lone Battery Life] — The small voice amplifier has a high capacity 2200mAh rechargeable Lithium Ion battery that provides up to 12 hours of operation from a fully charged battery.Charging is simple via a USB cable that is included. And it only takes 3-5 hours to fully charge. [Comfortable and Portable] — Portable loudspeaker comes with an adjustable band that you can use it to tie around your waist or hang on your neck. Teacher speaker amplifier has a clip on the back, you can clip on a belt or the pant waistband. The wired headset microphone is adjustable. [Stable Performance] — It is a original voice am