Pitney Bowes 4100 Operator's Manual page 25

Important: Please note that you would not be entering commas or
periods. Those typographical characters appear in our
instructions merely to serve their usual separative
functions and are not intended for actual entry from your
machine's control panel.
While there is a function (broadcasting) which requires the
entry of commas, we provide special ways to do that, as we'll
explain when the time comes.
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