Description/Features: 1. Rich interfaces and versatile design to meet the needs of different devices 2. Multiple connection methods, easy connection, no driver required 3. Upgrade Bluetooth 5.3 to reject delays and freezes. 4. CD-level high-definition lossless playback of sound, zero delay in listening to 5. Support U disk playback, plug and play, no driver required Specifications: Interface: RCA optical USB AUX Transmission rate: 100(Mbps) Working frequency: 2.4(MHz) Effective working radius: 10 (m) size: 6.7 x 5 x 2cm Material: plastic colour: black Package Contents: 1 x Bluetooth adapter 1 x 35 mm AUX audio cable 1 x RCA audio cable 1 x Optical audio cable 1 x Type-c charging cable 1 x English instructions Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.