Features: Mode switching: a. If the device has been in a mode for a long time, it needs to be re-energized twice to switch to another mode. b. If the device has just switched mode, you want to immediately switch to another mode, you only need to re-energize once. Pairing method RX mode: Pairing name: KN320, find KN320 in the Bluetooth settings of the phone to pair. The blue light flashes during the pairing process and the blue light stops flashing after the pairing is successful. Connect the product to the audio device with a 3.5 audio cable. TX mode: TX mode will automatically search for other Bluetooth receiving devices (such as Bluetooth headset, Bluetooth speaker, Bluetooth receiver, etc.), the red light flashes during pairing, and the red light stops flashing after pairing succeeds. Connect the product to a device such as a TV with a 3.5 audio cable/RCA audio cable. Super-Portable Audio-Streaming Power The KN320 is just 18mm (0.63") across and weighs only 18g (0.63oz), but 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. Broad 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. Specifications: Model: KN320 Technologies: BT5.0, A2DP, AVRCP (receiver mode only) Operation Range: Up to 10m / 33ft (without any blocking objects) Pairing name(Receiver Mode ): KN320 Transmitter mode: red LED light is on Receiver mode: blue LED light is on Dimensions: 32mm*17mm*8.5mm Color:Black Package Content: 1x Bluetooth 5.0 Audio Transmitter/Receiver Adapter 1x 3.5mm Aux Cable 1x User Manual Note: Please allow 0-2cm error due to manual measurement. pls make sure you do not mind before you bid. Due to the difference between different monitors, the picture may not reflect the actual color of the item. Thank you! ✅This extremely portable, lightweight wireless audio transmitter & receiver is an ideal wireless audio solution for a wide range of situations and uses ✅Transmitter mode: wirelessly streams audio from your non-Bluetooth TV, home stereo system, or CD player to your Bluetooth headphones or speakers ✅ Receiver mode: wirelessly streams audio from your Bluetooth-enabled phone, tablet, or computer to your wired stereo, speakers, or headphones