Connecting USB (Universal Serial Bus) with the traditional RS-232 serial port, this adapter connects cellphones, PDAs, digital cameras, modems, or ISDN terminal adapters through your USB (Universal Serial Bus) port. Has a data transfer rate of over 230 kbps. Since the adapter uses no IRQs, there are no IRQ conflicts, & it is ideal for when you need many serial devices attached to your PC. Frees your RS-232 port for other uses.