Fangrui Product Details Product Name: Bluetooth Decoding Board Product Model: Xy-wrbt Working Voltage: 3.7~24vdc Bluetooth Version: 5.0 Mission Distance: 15m (visible And Unobstructed) Signal To Noise Ratio: 90db Distortion: - 70db Number Of Channels: Dual Channels (stereo) Audio Interface: 3.5mm Audio Interface Module Protection Mechanism: Power Reverse Connection Protection 1. Micro-usb Mobile Phone Charger, 3.7-4.2v Lithium Battery And 3.7-24v Dc Power Supply Can Be Used For Power Supply. 2. Short Circuit The On/off Contact For 2 Seconds To Set The Decoding Board On/off. For Battery Power Supply, It Is More Power Saving To Turn Off When Not In Use, Which Is Convenient For Modification. Operating Instructions: After The Power Is Turned On, The Blue Indicator Flashes Quickly To Enter The Bluetooth Mode; After Broadcasting The Prompt Tone, Enter The Pairing Mode And Wait For Pairing; Mobile Phone Bluetooth Searches For Xy-wrbt (power Amplifier Board Device Name), Click Xy-wrbt To Connect, After The Connection Is Successf