1、The 2‑in‑1 bluetooth transmitter and receiver, as bluetooth audio transmitters, are specially designed for audio devices without bluetooth function (such as MP3, MP4, TV and PC, etc.). 2、Connect the bluetooth transmitter to audio device that does not have bluetooth via the included 3.5 mm audio plug, and change the audio device to an audio device that supports bluetooth, so that it can be used with bluetooth‑enabled headphones and speakers. 3、As bluetooth audio receiver, specifically designed for car stereo systems and home audio systems. It can change the traditional car stereo system and home audio system to a system that supports bluetooth, and can be easily paired with bluetooth‑enabled smartphones, laptops, and tablets. 4、Receiver mode, bluetooth receiver change the traditional speakers into bluetooth‑enabled ones. After paired, play music wirelessly from your bluetooth‑enabled smart phones, laptop, tablet, etc. Support automatic re‑connection. 5、Transmitter mode, bluetooth transmitter is designed for audio devices (such as MP3, MP4, TV and PC, etc.) without bluetooth function. The bluetooth transmitter can be connected to audio device via the supplied 3.5 mm audio plug, changed to an audio device that supports bluetooth, and used with bluetooth‑enabled headphones and speakers. 6、ANC noise reduction and AEC aftersound elimination. Support noise suppression and aftersound cancellation, offering you magnificent stereo sound & wonderful sound quality. 7、Perfectly compatibility for IOS / for Android smart phones, tablet PC, almost all audio devices that support Bluetooth and stereo systems with 3.5mm ports. 8、Low power consumption, built‑in 600mAh battery ensures up to 8 hours of working time, you can use wireless internet for free all day. Easy to use, no need to download any APP.