1. Using high-quality materials, product quality is guaranteed 2. Exquisite and compact appearance, easy to use 3. Stable performance, using QCC3034 chip 4. Linear power supply chip, fully audio-specific high-pass filter capacitors 5. Wide range of applications, suitable for modified audio amplifier situations Parameter: Power supply voltage: AC6-20V/DC6-20V/DC5V Current: 100MA Bluetooth chip: QCC3034 Decoding chip: PCM5102A Bluetooth version: 5.1 Support audio decoding formats: , AAC, , -HD If you are not professional for technology, please don't buy this product Warm reminder: This module turns on as soon as it is powered on. There is no need to any buttons. After powering on, the blue light flashes. After about 8 seconds, the blue light flashes quickly. Bluetooth enters pairing mode. At this time, you can use your mobile phone to search for Bluetooth. When Bluetooth BT is found Open the Speaker, click pairing to link Bluetooth, no password is required, and the blue light stay on after is successful. Now you can . Regarding the noise issue, this board uses PCM5102A audio decoder, linear power supply chip, and fully audio-specific high-pass filter capacitors. The board itself does not have any noise. However, if the power supply of the power amplifier is used, there may be common ground noise. Please use a separate power supply. Color:As Shown Material:PCB Package Contents: 1 * Bluetooth decoder board 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.