LG G5400 User Manual page 56

If you select this menu, you can receive an incoming call by only
opening the flip.
If you select this menu, you can receive a call by pressing any key
except E [End] key.
If you select this menu, you can receive a call by only pressing
S [Send] key.
You can send your phone number to another party. Your phone
number will be shown on the receiver's phone.
Your phone number will not be shown.
If you select this, you can send your phone number depending on
two line service such as line 1 or line 2.
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