This adapter creates cable-free connections between PCs and other Bluetooth devices such as Bluetooth enabled headsets?? speakers?? cell phones?? keyboard or mouse and more (with Microsoft built-in drivers) at speeds of up to 3 Mbps</br>Bluetooth 4.0 technology. Backwards compatible with Legacy Bluetooth Equipment Bluet" 3.0?? 2.1?? 2.0 and 1.0 Equipment??Improves Bluetooth support for Windows 10??8.1/8??7??Vista?? XP??2003?? 2000??Me?? 32 bit and 64 bit</br>Supports Bluetooth stereo headsets and more with built-in Windows 10 and 8 drivers or using the included drivers for Windows 7 and earlier. Specifically works with Microsoft's new Bluetooth 4.0 Low Energy support in Windows 8 and later. Does not add Bluetooth Low Energy.</br>Extremely compact USB adapter. Supports A2DP stereo playback?? Safe to leave in for laptop travel Newest Bluetooth class 2 Smart Ready specification with v 4.0 low energy.</br>Up to 33ft/10m?? wireless data exchange?? audio Music Stream Enhanced Data Rata (EDR) compliant for both 2 Mbps and 3 Mbps modulation modes with gold plated connector.</br></br>Product Description</br></br><b>Important Note:<br> When you connect headset or speaker??feel the sound like handsfree?? please You have to Uncheck "ony" from<br> the services setting on your bluetooth device -> Control Panel/Hardware and Sound/Devices and Printers -> <br> select your device and right-click?? open Properties?? then go to Services tab and uncheck Handsfree Telephony. <br> Marked as your default device in Control Panel -> Hardware and sound -> Change system sound -> Playback -> <br> select bluetooth device and select set defaults.</b><br> <br> CRS V4.0 Dongle<br> Support Bluetooth voice and date transmission<br> Ultra-compact?? easy carrying and space saving. <br> Experience stereo audio with Advanced Audio Distribution Profile (A2DP) support. <br> Bluetooth Low Ener