802.11ac (Wi-Fi 5) backward compatible with 802.11a/b/g/n. Max Speed: Typically up to 433 Mbps on the 5GHz band.
Visit the official Realtek Download Center to find the latest "WLAN USB driver" package.
If your adapter is not recognized or frequently disconnects on Windows 11, try these fixes: Realtek 8811CU Wireless LAN 802.11ac USB NIC - DriverHub