Features: Rich button functions, simple operation. Overheating, overcurrent, short circuit, anti-static for protection. APP-control, you can set a pass-word, adjust the volume of the prompt sound, switch the prompt sound, etc. Ten kinds of natural sounds Create unique natural sounds scenario, create a natural atmosphere, quickly calm down, and achieve deep sleeping. Support wuzhi-Audio, modify bt-name, pass-word setting, volume adjustment of prompt tone, on/off prompt tone, sleep aid, firmware upgraded, etc. Box pairing function, the wireless function enables two sets of speakers to be combined into left and right channel pair boxes, with a for stronger sense of spatial-positioning. Package Includes: 1x Amplifier Board Specifications: Material: Electronic Component Size: Approx. 75x70x20mm/2.95x2.76x0.79in Audio output: left channel 15W + right channel 15W + subwoofer 30W Adapter power supply: DC9-24V, 3A Adapter speakers: left and right channel 10-30W, 4-8, subwoofer 10-30W, 4-8 note: Please allow 1-2cm errors due to manual measurement, make sure that you do not mind before you order. Due to the difference between different monitors, the picture may not reflect the actual color of the item.