Features: BT 5.0 Adapter, this BT audio adapter support BT 5.0,you can use it to connect with many kinds of phone, stable and fast signal without delay. 2 modes with different LED light, this USB BT audio adapter Features a LED indicator light, so you can easily distinguish different mode. Blue light means receiver mode, red light for transmitter mode. Plug and Play. No drivers required, switch modes in one second. The button on the side to switch modes. Small and portable, but it has got powerful wireless audio streaming capabilities. Slip the 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. Specification: Color: Black Size: 32x17x8.5mm BT: 5.0 Package Size: 8x6.5x2.2cm/3.1x2.5x0.8in Package Weight: 15g/0.5oz Note: Adapter pairing name is B16. Package List: 1 x BT Receiver& Transmitter