Features: 2 in 1 Bluetooth Transmitter and Receiver, as a Bluetooth Audio Transmitter, B6 is specially designed for the Audio Devices (such as MP3, MP4, TV and PC, etc.) without Bluetooth function. You can connect the Bluetooth Transmitter to the audio devices without Bluetooth function via the included 3.5mm Audio Plug, changing these audio devices into Bluetooth-enabled audio devices, and making it work with Bluetooth-enabled Headset and Speaker; as a Bluetooth Audio Receiver,C28 is specially designed for Car Stereo systems and Home Audio System. It can change the traditional Car Stereo systems and Home Audio System into Bluetooth-enabled ones, and easy to pair with Bluetooth-enabled Smart Phones, laptop, tablet, etc. With this product, you can greatly enjoy music from your phone, laptop, tablet without the hassle of cables. Model number: C28 Bluetooth: V5.0 Battery: Built-in Rechargeable Li-polymer battery Working Time: 4 Hours Audio Port: 3.5mm Color:Black Main Item Size: 2.2 x 5.9 x 1.2cm / 0.86 x 2.32 x 0.47 in Package includes: 1 X Bluetooth TransmitterandReceiver Note: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement.