Specifications: Product Name: NFC Bluetooth 5.2 Audio Receiver Bluetooth version: 5.2 Forward transmission distance: 10 meters Interface: 3.5mm/Type-c Support: U disk; hands-free calling; NFC connection; SBC; AAC; 5V Micro USB power supply; two mobile phone connection. (Only receive function, does not support transmit function) Bluetooth protocol: AVRCP, A2DP Frequency range: 2400-2483.5MHz Frequency Response: 20Hz-20kHz Output power: 28mW RL=16Ω Signal-to-noise ratio: more than 90dB Total harmonic distortion: less than 0.1% Product size: 78*50*18 (mm) Features: Auto On When you connect to the power, So it's very good for use in the car or other you want it have auto on functions. Package includes: 1x Bluetooth 5.1 Audio Receiver Adapter 1x 3.5mm Aux Cable 1x USB Charging cable 1x User Manual or 1x Bluetooth 5.1 Audio Receiver Adapter 1x 3.5mm Aux Cable 1x USB Charging cable 1x RCA Cable 1x User Manual (PS: If you did not select the ''with RCA Cable'', RCA Cable will not include)