AT&T System 25 - Manual (Page 52)

Pickup
Pickup allows you to answer a call that is ringing at another
telephone. All multiline telephones have this fixed feature.
Picking Up Calls
1 Listen for dial tone, then press
2 Dial the extension number of the ringing telephone.
Picking Up Calls in Your Pickup Group
1 Listen for dial tone.
2 Press
NOTE: Your System Administrator will notify you if you
have been designated to be in a pickup group. (This is an
assignable feature. )
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