SPECIFICATION: Bluetooth V5.1 Support protocol RX: A2DP AVRC TX: A2DP Operating frequency band 2.402GHz - 2.480GHz Interface type: input: 3.5mm interface/output: 3.5mm interface Built in battery 150mAh Charging time is about 2 hours Endurance time RX is about 8H, TX is about 5H Bluetooth distance 10 15M (open place) Charging method Type-c DV5V Size 66 x 20 x 12MM Weight : 11g Applicable scenes Various speaker/car/computer/TV/power amplifier and other scenes FEATURES: 1.BLUETOOTH COMPATIBLE: This audio Bluetooth adapter support 3.5mm aux audio, and also compatible with all smartphones, bluetooth audio devices (Bluetooth headphones, Bluetooth speakers and much more), and stereo equipment with audio input port. By pressing the button on the center front, the receiver and transmitter device will start to pair to the next Bluetooth device. 2.TRANSMITTER RECEIVER MODE: 2in1 design, by using this wireless adapter, you can send and receive all of the audio freely and easily. Transmitter enables your TV, AV Receiver, Radio and other home audio source devices to stream music to your Bluetooth headphones or speakers Receiver lets non-Bluetooth devices like your home stereo or AV Receiver and wirelessly stream music from your cellphone/PC. 3.CLEAR SOUND: A2DP support voice prompts, gets high-quality audio sound, offers you 30 feet operation range with good performance, gives you a good experience when answering the phone or watching late-night shows. In order to get clear sound, we recommend NOT using the 3.5mm Bluetooth transmitter-receiver while charging. 4.WIRELESS FUNCTION: Want to watch football/baseball / Boxing / Golf / NBA game late at night without waking anyone up This is a great chose for you. Bluetooth transmitter function wirelessly streams audio to Bluetooth speakers or headphones from your TV or older media devices like portable CD players that lack built-in Bluetooth. 5.Built-in Mic: Bulit-in mic, so you can use it to handsfree call. Package included : 1 X Bluetooth TransmitterandReceiver 1 X USB Charging Cable 1 X User Manual 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.