Product information: Color: black Operating range: maximum 10m (without obstacles) Pairing name: KN321 Charging time: 2 hours Interface: USB 3.5mm audio Battery type: lithium polymer (200mAh) Size: 44 44 12mm Weight: 18g Packing list: 1 x Bluetooth 5.0 Audio Transmitter / Receiver Adapter, 1 x Micro USB Power Cord, 1x RCA Cable, 1x 3.5mm Auxiliary Cable, 1x User Manual Features: 1. This portable, lightweight wireless audio transmitter and receiver is a ideal wireless audio solution for various situations and applications 2. Transmitter mode: wirelessly transmit audio from a non-Bluetooth TV, stereo or CD player to a Bluetooth headset or speaker 3. Receive mode: transmit audio wirelessly from Bluetooth-enabled mobile phones, tablets or computers to wired stereos, speakers or headphones 4. Simply press the switch to switch between transmitter and receiver modes. Use advanced Bluetooth technology and 3.5mm audio cable (included) for easy connection. 5. Ultra-portable audio streaming power adapter KN321 is only 44mm (1.73inch) in size and weighs only 18gram (0.63inch) but has powerful wireless audio streaming function. Slip this transmitter and receiver into your backpack or laptop bag and take it with you with ease. 6. Wide Compatibility: This receiver transmitter adapter is equipped with 3.5mm cable and 3.5mm 2 RCA cable, widely used in computer, laptop, home stereo, earphone, smartphone, MP3 player , CD players, etc.