1. Transmission Mode: The Usb Power Supply Tx Indicator Light Lights Up, And The Device Will Automatically Enter The Pairing Search State. Turn On The Bluetooth Device Such As A Bluetooth Headset/Speaker And Enter The Pairing Mode. The Device Will Automatically Search For A Successful Connection. 2. Transmission Mode: Connect The Type-C Data Cable To The Adapter For Power Supply, Plug In The Audio Cable, The Device Will Automatically Recognize The Audio Input, And The Device Work Indicator Light Will Always Be On. The Data Cable Is Connected To The Pc And Usb/Audio Is Recognized. The Device Working Indicator Light Flashes Slowly. 3. Receiving Mode: When The Rx Indicator Light Light Up, And The Device Will Automatically Enter The Pairing Search State. Turn On The Bluetooth Of Mobile Phones/Tablets/Computers And Other Devices To Search For The Product Name "Bls -B55" Click To Connect To Bluetooth. The Device Is Successfully Connected, The A Indicator Light Of The Device Lights Up. 4. Receiving Mode: Double-Click The Button Again, And The Device Will Initiate A Pairing Search. The Mobile Phone Search Connection Is Successful, And The B Indicator Light Of The Device Lights Up. 5. Receiving Mode: The Device Working Indicator Light Flashes Slowly While Breathing. (Indicates 3.5mm Audio Output). Short Press The Button To Pause/Play, Press And Hold For 5 Seconds To Clear The Pairing Record, The Response Indicator Will Flash 3 Times. 1.Bluetooth version: Qualcomm 5.3 2. Bluetooth protocol: A2DP HFP 3. Frequency range: 2.402GHz-2.480GHz 4. Frequency response: 100Hz-20kHz 5. Transmission distance: 20 meters 6. Number of connected devices: 2 Note: Different Batches May Have Differences In Product Appearance, Color, And Printed Characters, Which Will Not Affect The Use Colour:As Shown Material:Plastic Package Contents: 1x Bluetooth Adapter 1x Charging Cable 1x 3.5 Audio Cable 1x Instructions In Chinese And English 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.