It has below functions for model 323-2SD 1. Work with GSM SIM card. 2. Easy to be installed. 3. Could store 4 access numbers. ---new function! 4. Could reroute use’s call after programming the specified access number and PIN codes. ---new function! 5. Could set prefix go though or by pass the dialer. ---new function! 6. support prefix removing function---new function! 7. Intelligent auto pickup least cost route (LCR) function ---new function! 8. Support four working mode: a. carrier select mode b. force carrier select mode c. call through wait for connection establish d. call back 9. No need to change user’s conventional dialing habit: a. Support dial from the Contacts and phone book, no need to memorize and input the numbers. b. Support dial directly from mobile phone's missed calls/ call record/ call history/ recent calls. 10. Compatible with many mobile phones, Nokia, Motorola, Sony Ericsson, Samsung, LG, and so on.