Working Voltage: DC 3.7V~5V Bluetooth Version: 4.2 Class: D Output: 5W+5W Speaker: 4ohm~8ohm 3W~5W Signal-to-Noise Ratio: 90dB Noise Level: -70dB Crosstalk: -86dB Dynamic Noise Reduction: 91dB Support Profile: A2DP/AVCTP/AVDTP/AVRCP/HFP Line of Sight Range: 15m Work Temperature: -40C ~ 85C Work Humidity: 0%~95% RH Size: 38x38x7.5mm Using Steps 1. Connect 2pcs 4ohm~8ohm 3W~5W speaker at "R_OUT" and "L_OUT". Or connect to a speaker from 3.5mm audio output interface. 2. Connect right power supply at Micro-USB or PCB silk screen at "3.7-5V". 3. The Blue LED indicator will stay ON, indicating the module has entered Bluetooth mode. 4. The module emits a tone, indicating it is waiting for pairing. 5. Enable Bluetooth on your phone and search for Bluetooth device. Click to connect the module. When the tone is heard again, pairing is successful. If pairing fails, turn off Bluetooth, remove power, and retry pairing. 6. Start playback. Note: During use, ensure there are no obstacles such as walls between the mobile phone and the Bluetooth decoder board. Keep the device away from metal shielding. Obstructions may reduce transmission distance and cause playback interruptions. Adjust the angle between the decoder board and the mobile phone to achieve optimal signal connection. Application: 1. DIY speaker 2. Voice intelligent control 3. Bluetooth signal conversion 4. Stereo Bluetooth speaker 5. Stereo Bluetooth headset 6. Bluetooth hands-free calling 7. Bluetooth control 8. Multimedia equipment Color: Red Material: ABS Package Contents: 5 x Bluetooth MP3 Decoder Amplifier Note: Light reflection and different displays may cause the color of the item in the picture to vary slightly from the actual product. Measurement error allowed is +/- 1-3cm.