Adopt Bluetooth 5.0 chip design, which has stronger compatibility and stability. 2 in 1 design of Bluetooth receiver (RX) and Bluetooth transmitter (TX), toggle switch for quick switching. Equipped with a high-definition LED digital display screen, the working status and Bluetooth mode are clearly visible. Built-in digital-to-analog chip, supports six signal interfaces: digital optical, coaxial, AUX, RCA, USB drive, and TF card. Upgrade with NFC function, allowing the mobile phone to connect easily. Bluetooth version: Bluetooth V5.0 Supported protocols: A2DP, AVRCP TX: A2DP Working frequency band: 2.402GHz - 2.480GHz Power level: Power level 2 (Class II) Sensitivity: -85dBm, less than 0.1% BER Signal-to-noise ratio: 90dB Distortion: 0.1% Interface Type: Input: 3.5mm AUX + RCA + optical (Optical) + coaxial (Coaxial) + USB + TF interface Output: 3.5mm AUX + RCA Fiber parameters: support fiber input, 16M, sampling rate 96kHz Supported formats: MP3, WAV, WMA, FLAC, G729, M4A, ALAC, DTS, MIDI, G726, MTY Screen size: 32 x 14.5 x 7mm Working current: Less than 40mA Built-in battery: 3.7V / 500mAh, 1.85Wh Charging current: about 500mA Charging time: about 1.5 hours Battery life: about 10 hours (RX), TX about 8 hours Bluetooth distance: 10M - 15M (open area) Charging interface: Type-C 5V - 0.5A Compatible devices: Android, iOS system mobile phones and tablets, active speakers, power amplifiers, and Bluetooth speakers or headphones that support A2DP/AVRCP protocol. Product size: 92 x 65 x 20mm Type: NFC Bluetooth Adapter Transmission rate: 100 Mbps Bluetooth standard: 5.0 Working frequency: 2.4 GHz Color: Black Material: PC Package Contents: 1 x Bluetooth Adapter 1 x Type-C Charging Cable 1 x 3.5mm Audio Cable 1 x Red and White RCA Cable 1 x IR Remote Control 1 x English Manual Only the above package content is included; other products are not included. Note: Light reflection and different displays may cause the color of the item in the image to be slightly different from the real thing. Measurement allowance is +/- 1-3cm.