AT&T MERLIN LEGEND Analog Direct-Line Console Operator's Manual page 96

Programming Special Characters
Press You see
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A-4 P r o g r a m m i n g S p e c i a l C h a r a c t e r s
Description
For
End of Speeds call processing by the
Dialing system. Use at the end of a
programmed sequence of
numbers to indicate you have
finished dialing or to separate
one group of dialed digits from
another.