Feature:1. You can DIY a for Bluetooth speaker, just need a battery(this product doesn't include battery), two speakers, and a case then you will get a nice for Bluetooth speaker.2. Output 5W + 5W dualchannel stereo audio, support USB sound card, no driver, just plug and play.3. Mini for Bluetooth audio receiver board updates to for Bluetooth 5.0 version, which is compatible with most mobile phones and for Bluetooth adapters.4. The mini for Bluetooth audio receiver board is updated to for Bluetooth 5.0 version, compatible with most mobile phones and for Bluetooth adapters.5. The maximum transmission distance is about 15 meters, and the power consumption in standby mode is ultralow.Specification:Item Type: Power Amp ModuleVoltage: 3.7V-5VCurrent: 1.5A-2APower: 5W + 5WFor Bluetooth: 5.0Speaker: 4/3W (not included)Screw Hole Diameter: Approx. 1.6mm / 0.1inSize: Approx.40mm / 1.6in22mm / 0.9in27mm / 1.1in34mm / 1.3in.Package List:2 x Power Amplifier Board6 x Connection LineNote:1) B+ is connected to the positive pole of the power supply from DC3.7V to 5V+, and N is connected to the negative pole;2) Working voltage lithium battery 3.7V, or regulated power supply DC 4.55V DC, current (600700MA when connected to one speaker; 1.52A when connected to two speakers. Lithium battery powered speaker with 43W+3W, regulated power supply 5V /2A, speaker with 4 ohms 5W+5W. If the current is not enough, there will be skipping or for Bluetooth instability, the motherboard will always restart or the sound quality/broken sound/distortion, etc. (If there is this problem, please check your power supply) ,The voltage cannot be higher than 5V, otherwise it will damage the main chip, power amplifier IC and related components, please pay attention3) White 2P seat SP/SP+ from bottom to top LO/LO+ connected to speaker 1; white 2P seat SP/SP+ from bottom to top RO/RO+ speaker 2