Specifications: Model: KN318 Technologies: BT5.1, A2DP, AVRCP Operation Range: Up to 10m / 33ft Pairing name: KN318 Pairing: blue LED flashing Paired successfully: The blue light keeps on Dimensions: 32mm*17mm*8.5mm Color: Black Mode switching: Receiver USB Mode: The USB mode does not need to use 3.5 audio cables. It can be directly plugged into the car USB interface and speaker USB interface and can be used directly after pairing with the mobile phone. Note: The car USB interface and speaker USB interface must support USB audio output. Receiver AUX Mode: AUX Mode needs to connect one end of the 3.5 audio cables to the kn318 audio interface, and the other end to the car's 3.5 audio interface and speaker 3.5 audio interfaces, and it can be used after pairing with the Bluetooth of the mobile phone. Bluetooth hands-free calling: Built-in microphone, when the mobile phone is talking, you can make hands-free conversation through the microphone on KN318, which is very convenient to use in the car. Package Content: 1 x Bluetooth 5.1 Audio Receiver Adapter 1 x 3.5mm Aux Cable 1x User Manual 1. This extremely portable, lightweight wireless audio transmitter & receiver is an ideal wireless audio solution for a wide range of situations and uses. 2. Transmitter mode: wirelessly streams audio from your non-Bluetooth TV, home stereo system, or CD player to your Bluetooth headphones or speakers 3. Receiver mode: wirelessly streams audio from your Bluetooth-enabled phone, tablet, or computer to your wired stereo, speakers, or headphones 4. Portable Audio-Streaming Power, has got powerful wireless audio streaming capabilities. Slip this transmitter & receiver into your backpack or laptop bag and take it on the go without the slightest effort. 5. Wide Compatibility: With the included, 3.5mm cable, this Receiver Transmitter adapter can widely be used on your computer, laptop, home stereo system, headphone, smartphone, Mp3 player, CD player, etc.