Product Name: USB Bluetooth Adapter Bluetooth Version: Bluetooth 5.4 (+BLE low power consumption, low latency) Transmission distance: 20 meters (under barrier-free environment) Supported protocols: A2DP, , AVRCP, HID, ACC, etc. 5.4 Bluetooth, dual-mode dual-channel, compatible with Bluetooth 2.0, 3.0, 4.0, 5.0, 5.1, 5.3 specifications. Intelligent low-power chip, RF transceiver, provides lower latency, flexible and powerful Bluetooth applications Support Cass2 power level 20 meters (in open environment) Support Bluetooth 5.4 dual-mode specification (LMP 13.X true Bluetooth 5.4 standard) Support USB2.0/3.0 interface Support multiple devices to connect at the same time (up to 7 devices can be connected) Operating temperature -20 to 70 Support : 8.1, 10, 11 (driver-free, plug and play) Windows7 driver can be installed and used Support protocols: HFP/ (hands-free phone/headset) A2DP/AVRCP (stereo music) HID/HOGP (keyboard and mouse)/ACC.Android smartphones, etc. Colour:As Shown Material:plastic Package Contents: 1 x Bluetooth 5.4 USB Adapter Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.