Zte A12 User Manual page 28

Making DDD: Enter telephone number by Number Keys (add area code when
making a long distance call), and then press Send Key to send a call. Hang up the
phone by End Key if the call is over.
Dialing extension number:
Method 1: Dial the telephone exchange and then the extension number.
Method 2: Enter the telephone exchange number, hold # Key to enter pause character
"P", enter the extension number, and then press Send Key. Then your phone will dial the
extension automatically after getting through the exchange. Like this:
Area code Exchange number
Making IDD: Hold * Key until your screen displays the character "+" (replaces the
P Extension number Send Key
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