Main Function:
1. Landline connection (GSM optional)
2. Dual-talk mode and single-talk mode switch freely
3. System with a speaker and a button that can press to talk, instead of having to pick up the phone
4. Special picture designed button that make user easy to remember and operate
5. Get through emergency calling in priority
6. Wired/wireless remote call for help
7. Telephone line get through/breakup situation check
8. Built-in battery low power report
9. Host can be forcing set in ARM situation, it works when power on.