USB to 4 serial port expander.Adds four RS-232 serial ports to the DASDEC through a USB connection.Digital Alert Systems part number USB/4RS232.DAS USB to 4 serial port expander (USB/4RS232)SKU: USB/4RS232$350.00PriceExcluding Sales Tax | Shipping PolicyQuantity*Add to CartBrandDigital Alert SystemsProduct DetailsManufacturer: Digital Alert SystemsManufacturer part number: USB/4RS232Sold by: Radio Gearheads, 705 Eaton Ave N, Fosston, MN 56542 Questions about compatibility, licensing or lead time? Call 1-800-992-1506 or use Get A Quote.