AT&T 8102 User Manual page 9

Before you begin to use the procedures described in this book check
which type of telephone you are using by looking at the designation
number at the top right corner on the front of your telephone. Then, see
Figure 1, the 8102 telephone, or Figure 2, the 8110 telephone,
according to which telephone you are using, and read the explanations
of their features.
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