More stable for dual-channel 3.5MM interface B2 usb Bluetooth transmitter and receiver equipped with 2 3.5mm audio interfaces. Let the input and output not interfere with each other. It will work more stable. Fast And Further Fast and further working distance than Bluetooth 4.0 Supports Bluetooth speakers, headphones, headsets, keyboards, mice, and more. B2 can work with Bluetooth speakers and stereo headphone maximum transfer rate up to 3Mbpsand transmission distance up to 33ft/10M in open space. (NOTE: Operation range can be affected by physical obstructions and wireless interference)