Gaoxinqi HA39922P/T intercom telephone comes with a flash function, which is a programmable button that alerts the phone switch when a feature, like Call Back, Message, or Voice, is used. Also, pulse dialing is available, which uses a series of clicks to represent each digit in the phone number, one after the other. Then, a small pause would be required in order to separate one digit from the other. Additionally, features tone dialing that also known as dual-tone multi-frequency, which utilizes various tones to indicate