Yealink SIP-T2 SERIES Administrator's Manual page 465

Configuring Basic Features
Parameters Permitted Values Default
X ranges from 1 to 29 (for SIP VP-T49G/SIP-T48G)
X ranges from 1 to 27 (for SIP-T46G/T29G)
X ranges from 1 to 15 (for SIP-T42G/T41P)
X ranges from 1 to 21 (for SIP-T27P)
X ranges from 1 to 3 (for SIP-T40P/T23P/T23G)
X ranges from 1 to 2 (for SIP-T21(P) E2)
For ext keys:
X ranges from 1 to 6, Y ranges from 1 to 20, 22 to 40 (Ext key 21 cannot be configured).
Example:
linekey.1.value = *88
Note: It is not applicable to SIP-T19(P) E2 and CP860 IP phones.
Web User Interface:
DSSKey->Line key->Value
Phone User Interface:
Menu->Features->DSS Keys->Line Key X->Value
linekey.X.label/ String within 99
Blank
expansion_module.X.key.Y.label characters
Description:
(Optional.) Configures the label displayed on the LCD screen for each DSS key.
For line keys:
X ranges from 1 to 29 (for SIP VP-T49G/SIP-T48G)
X ranges from 1 to 27 (for SIP-T46G/T29G)
X ranges from 1 to 15 (for SIP-T42G/T41P)
X ranges from 1 to 21 (for SIP-T27P)
X ranges from 1 to 3 (for SIP-T40P/T23P/T23G)
X ranges from 1 to 2 (for SIP-T21(P) E2)
For ext keys:
X ranges from 1 to 6, Y ranges from 1 to 20, 22 to 40 (Ext key 21 cannot be configured).
Note: It is not applicable to SIP-T19(P) E2 and CP860 IP phones.
Web User Interface:
DSSKey->Line Key->Label
Phone User Interface:
Menu->Features->DSS Keys->Line Key X->Label
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