Audio input: 3.5mm stereo input, USB audio input ,Bluetooth 5.0 ,RAC input, TF card, USB input (can be connected to computer, mobile phone, OTG) Using TPA3116 chip, the maximum power can reach 50W, with 12V 5A, the actual output power reaches 30W*2, 4 ohms Hi-Fi sound and Powerful: HiFi clear and clarity sound, no audible noise, our spent a lot of time and efforts to optimize the circuit to it has no noise even at the maximum output power. Long Press the Switch Turn On Output power: 50W+50W Power requirements:DC9V-24V Bluetooth distance: At least 12m ( No obstacles) Bluetooth agreement: Bluetooth 5.0 Speaker Impedance: 4-16 Colour:Black Material:plastic Package Contents: 1 x Digital Audio Power Amp Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.