Special smart IP card,4 group IP for choice, high quality voice, 30 incoming call, 10 outgoiing call ... back, de 1. Special smart IP card,4 group IP for choice2. 1 service hotline, more convenient, pleasant to use the ... be called back, reviewed and deleted5. 5 step LCD contrast for your various requirement6. Dialing speed adjustable7. Music on hold function8 ...