1) Stackable: suitable for business use 2) Convenient: no need to dial card numbers and PIN codes and get through instantly after directly dialing the target phone number 3) Swift: mute synchronization preemptive dialing technology makes users get through within shortest time 4) Automatic: automatic switch and can automatically choose corresponding IP card according to the opening region 5) Safe: can set up private password and systematic password to prevent others from peculating and modifying system parameters 6) Compatible: compatible with IP card, local call card, 200 card, 300 card and other network cards 7) Multi-function: suitable for public use, family and company telephones, and extension lines of PABX systems 8) Great capacity: stores up to 9 groups of 60-digit IP card numbers and can store 600 groups of opening regions 9) Remote maintenance: remote programming function