rapidship929 Store TOSHIBA STRATA DK RSIU1A CARD RSIU 4 PORT SERIAL CARD YOU ARE looking ON A TOSHIBA RSIU1A 4 PORT SERIAL INTERFACE CARD. THIS CARD WILL WORK ON DK280 & DK424 TOSHIBA PHONE SYSTEMS.TESTED AND WORKING GOOD![!brand:toshiba!][!mpn:RSIU1A!]