Bluetooth version: 5.0 (without sunscreen, 15 meters)Output channel: 2.0 channelChip model: AP3050DWorking mode: class DAudio input: support bluetooth 5.0,AUX, U disk PlayRated output : 50W+50WFrequency response: 20Hz to 20KHzWorking voltage: DC8V to DC26VRecommended voltage: DC19VFit speaker parameters: 4-8 ohmsNOTE:1.For DIY---The outer casing is a material package, It needs to be assembled by itself, and the material package is given a screwdriver.2.---Attention The heat sink tape glue needs to be pasted to the chip by itself.3.For use---The switch on the board is standby switch. After the switch is off, the machine is in standby state with low consumption. If the is completely turned off or the DC plug on the machine can be unplugged for a long time.Colour:blackMaterial:PCB+Plastic+MetalSize:56 x 50 x 18mm Package Contents:1 x amplifier board1 x terminal1 set x shell material packageOnly 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.