Check the listing for details. GTMedia Bluetooth 5.1 Transmitter Receiver Optical AUX Coaxial USB Audio Adapter. Color: Black, Condition: New. Listed at 29.99 USD. Description:A4 is a Bluetooth 5.1 Receiver and Transmitter audio adapter, which it can compatible with all mobile phones and tablets. It can be used in cars and also works with computers, TVs, older version speakers, etc. Whether you are studying, living or working, you can share audio at any time.Features:- Bluetooth 5.1 audio adapter - Bluetooth receiver mode - Bluetooth transmitter mode - Wireless reception range: ～15m/49.2ft - Built-in 3.7V/800mAh battery enables long standby timeSpecifications: - Product model: A4 - Bluetooth version: V5.1 - Support protocol: RX: A2DP/AVRC, TX: A2DP - Frequency range: 2400-2483.5MHz - Sensitivity: -81dBm, 10m barrier-free - Frequency response: 20Hz-20KHz - Signal-to-noise ratio: ≧75db - Audio Performance: SBC AAC decode - Interface type: Aux in/out 3.5MM audio*1, RCA R/L - Basic function: Bluetooth receiver/Bluetooth transmitter - Use method: Plug and play - Supported equipment: Mobile phone/tablet/PC/TV/speaker/amplifier/headset/projector/mixers and other equipment with audio input/output interfaces - Power supply mode: Type-C interface- Input parameters: DC 5V⎓500mA (1A max) - Battery capacity: 3.7V/800mAh 2.96Wh - Duration: About 6～8 hours (Charging time: about 2 hours) Package Included:1 x Bluetooth audio adapter1 x Antenna1 x Remote control 1 x Instructions