Panasonic KX-T336 System Reference Manual page 102

Description of Assigning Items
Expansion Shelf
TSW Additional CONF
Conditions
None
Function
Enables the expansion shelf 1 when set to "1 Shelf" and both
expansion shelves 1 and 2 when set to "2 Shelves."
Enables the expansion of conference trunks when set to "Yes."
The following functions appear on the function line of this setting screen.
COMMON (SHOW LV, CHG LV, INS, OUS, REMOVE, EXIT) and HRD CPY keys
are available in this setting screen.
For operation, refer to Section 7-i "Operation of Function Keys."
9-c-2