NEC ESIB(8)-U20 Digital Station Card (Refurbished)The Electronic Station Interface ETU contains 8 circuits. Each circuit can support one digital multi line terminal (Electra Elite IPK, Electra Elite, Dterm Series E or Dterm Series i set, Message Display Board, Attendant Add On Console, Single Line Telephone adapter, Dterm Cordless Terminal, Dterm Extender or Electra Mail CTI port). Key Features: ESIB(8) U10 can mount ESIE(8) U10 as piggy back. For use with the NEC Electra Elite IPK phone system