Feature: 1. Using Bluetooth 5.0, the signal is more stable and the sound quality is better. 2. You can use Micro‑USB mobile phone charger, 3.7‑4.2V lithium battery and 3.7‑24V DC power supply. 3. Made of high-quality electronic component materials, stable and reliable performance. 4. Short-circuit the on/off contact for 2 seconds to set the decoder board on/off. 5. The module has the characteristics of anti-reverse connection, wide voltage operation, automatic return connection, and rechargeable lithium battery. Specification: Item Type: Bluetooth Decoder Board Material: PCB Application: Wide voltage and volume adjustable speaker power amplifier Working Voltage: 3.7~24V DC Bluetooth Version: 5.0 Transmission Distance: Approx. 15m / 49.2ft (visible without obstruction) Signal-to-noise Ratio: 290dB Distortion: ≤-70dB Number of Channels: Dual channel (stereo) Audio Interface: 3.5mm audio interface Module Protection Mechanism: Power reverse connection protection How to use: After the power is turned on, the blue indicator light flashes quickly and enters the Bluetooth mode; after the "prompt tone" is broadcast, it enters the pairing mode and waits for pairing; the mobile phone Bluetooth searches for "XY-WRBT" (the name of the power amplifier board device). Click "XY-WRBT" to connect, after the connection is successful, the "prompt tone" indicator light will be on, you can play mobile music, and the indicator light flashes slowly when playing music; after the Bluetooth is disconnected, the amplifier board prepares for the next pairing and playing. After the prompt tone, enter the pairing mode and wait for pairing. Package List: 1 x Bluetooth Decoder Board