Features:Digital Power Amplifier: Lossless sound quality, BT 5.0 transmission, stable signal and 12m long transmission distance without obstacles.Drive-free, plug and play. It can be connected to PC, laptop, smart phone, tablet, CD player, music player, TV, set top box, etc.Supports U-disk and TF card playing, compatible with various formats (MP3/ MAV/ APE/ FLAC). Compact and lightweight, easy to carry.Adopts MA12070 chip, the real output power can reach up to 50W for each channel, 2 channels in total; equipped with 12V 5A power adapter, the output power is 30W x 2 (4 ohms); if connecting with 8 ohms speaker, the output power is 15W x 2; please noted the required voltage is DC 9V-20V, the chip will be damaged if exceeding 20V.It is a constant resistance amplifier, supporting 4/ 6/ 8/ 16 ohms passive speakers; cannot be connected to active speakers and passive subwoofer; 4 pillars in the back are output interfaces, which cannot be connected to 3.5mm headphone plug or lotus plug.Note:1. Power amplifier and power adapter included only, other accessories are NOT included.2. Size and color may be slightly different due to manual measurement and different light conditions. Thanks for understanding.