Siemens Standard, Advance, Advance Plus, Advance Conference Telephone Manual page 40

To dial using a station speed code,
1. When your phone is idle, press the Menu key.
2. Select Speed dial features?.
3. Scroll to Station speed dial? and select it.
ENTER INDEX: will be displayed.
4. Dial the station speed dialing code.
OR
Press the Station Speed (SPEED) key, and dial the station speed
code. Or get a dial tone, dial # 3, and then dial the station speed
code.
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