USB Quad Serial Adapter instantly adds four RS-232 serial communication ports to your system. Full RS-232 modem control signals and hardware/software flow control RS-232 data signals: TxD, RxD, RTS, CTS, DSR, DTR, DCD, RI, GND High speed serial port with the baud rate up to 921.6K bps OS Compatibility: Windows 11, 10, 8, 7 and Vista (32 and 64-Bit) as well as Linux and Mac OS 10.X