Features: Rare earth material speaker, digital sound reinforcement technology, 8W high-power audio output, ensure good sound quality, loud sound. In addition to amplify voices, it can connect to MP3 player, smart devices via AUX input, as a small speaker, playing favourite music. Built-in large-capacity lithium battery, energy-saving, supports about 2.5 hours of quick charge, about 15 hours of use, long service time. LED light indicates the real-time working status of the sound amplifier. Rotary knob is for easy power on/off and volume control. Lightweight mini amplifier, mini size, novel and stylish appearance, can be worn with a waist or shoulder strap, very convenient. Specifications: Material: Metal Color: Black / White (Optional) Package Size: 18.5*14*6.5cm / 7.28*5.51*2.55in Package Weight: 320g / 11.28oz About Amplifier Frequency Response: 150Hz-12KHz Power: 8W Speaker Impedance: 4 Ohm THD: THD less than 1percent 1KHz@4R, 4W Operating Voltage: 3.45V-4.2V Battery Type: Li-ion Battery Battery Capacity: 3.7V/1800mAh Charging Port: Type-C Charging: 5V--800mA Charging Time: About 2.5h Operation Time: About 15h Weight: About 148g Dimensions: 92mm*72.5mm*25mm About Headworn Microphone Cartridge: Back Electret Cartridge Polar Pattern: Unidirectional Frequency Response: 60Hz-16KHz Sensitivity: -48.5dB+/-3dB (0dB=1V/Pa, at 1KHz) Note: Sound amplifier set only, others in pictures are not included. Due to manual measurement, there may be deviation. Due to lights or others, it may slightly differ from pictures. Packing List: 1 * Amplifier 1 * Headworn Microphone 1 * Waist Strap Clip 1 * Strap 1 * Charging Cable 1 * User Manual