Panasonic KX-T336 System Reference Manual page 330

Note:
Parallel connection assignment is available only when PITS telephone interfaced with
HLC card is selected.
If PITS telephone
interfaced with PLC card is selected, '+++" will appear in Parallel
Connect field and parallel connection assignment is not available.
02 If PITS telephone KX-T123230D is connected, select 04: KX-T123235
(7130), for PITS Model.
For OHCA Circuit, Intercom Number, Next Hunt Station, refer to Section 9-G-l .Ol
"Station (l/3)."
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