New Mini USB Bluetooth Adapter CSR4.0 Dual Mode Receiver for Windows 10/8/7/XP V4.0 Main Features:  technical specifications of Bluetooth 4.0  backwards compatible with Bluetooth 2.0 / 2.1 / 3.0 version  dual-mode transmission  Long transmission distance: Up to 20m - 50m transmission distance (no blocking), strong signal    Stable transmission rate: 3 Mbps transfer rate, providing high-speed file, audio data transmission CSR-driven management software: CSR Harmony-driven management software easy to use and  powerful, supporting multiple application extension Ultra-low latency link speed, intelligent wake-up energy-saving, 24-bit CRC checksum against of  interference, adaptive frequency hopping to reduce cross talk Compatible with  Windows 10 8/ Windows 7/ Vista/ XP  Mac iOS