& 12304;Multi-function Bluetooth transmitterreceiver& 12305; In TX Mode: Transfer your music from a TV, CD player, Ipod, laptop to a Bluetooth headset or stereo (You can connect two devices at the same time); In RX Mode: will transfer the music in your mobile phone or computer to the audio, so that you can enjoy HIFI CD freely The sound quality. Bypass mode: cable connection between TV and Speaker, you no longer need to plug/unplug any wires,easily switch it to other two mode. & 12304;262FT Ultra Long Range& 12305; & 12304;The Ultimate Listening Experience& 12305; Support low latency, virtually eliminating visual and auditory delays, you can simultaneously steam audio to 2 Bluetooth headsets, making VIKEFON BT-B15 bluetooth headphones become the best choice for watching TV and movies. Note: In order to achieve this low latency, your receiving setup must support low latency. & 12304;USB Rechargeable& 12305; It has built-in 500mAh battery, this is a UNIQUE feature compared to similar products, you can use it in any situations even there is no AC outlets. It can be fully charged in 2.5 hours but allows for more than 8 hours in TX mode 10 hours in RX mode of solid use, which is ideal for listening all day or on a long road trip, also you can use it while charging. *Note: This product will automatically enter the dormant and power-saving mode after 6 minutes without connection. & 12304;Easy Set Up, Easy Use& 12305; Supports remember your setting after power failure. Supports AUX / 2 RCA audio output standards making it compatible with 99% of the TVs on the market(NOTED:Don't support Digital OPTICAL),If you need support Digital OPTICAL,please select our BT-B21 or BT-B22 etc.Setup is a snap simply connect your transmitter/receiver to an outlet and your audio system, pair it to a phone or tablet and enjoy the music. Product main parameters: Bluetooth chip: CSR Chip Bluetooth version: V5.0 Bluetooth protocol support: RX:A2DP AVRCP TX: A2DP Transmission distance: 80M (Open Area) Battery standard: 500MA Working time: RX10H ;TX8H Charging time: about 2.5H Charging voltage: DC 5V Audio output mode: RCA, 3.5MM stereo audio interface CODEC: TX: Aptx LL HD,APTX,SBC,FS; RX: Aptx LL HD,Aptx,SBC,AAC,FS. What's in the box? 1x Bluetooth Adapter 1x 3.5mm Audio Cable 1x USB charging cable 1x RCA Audio Cable 1x User's manual