Panasonic KX-TD500 System Reference Manual page 1096

Conditions
This screen cannot be selected from "Special Attended-Submenu," if
"Configuration-Slot Assignment" has no DISA card programmed.
Tenant
Pressing the TAB key moves the cursor as follows:
Function
The following functions appear on the function line of this setting screen.
1 COMMON 2
COMMON (SHOW LV, CHG LV, INS, OUS, REMOVE, EXIT) and HRD CPY keys
are available in this setting screen.
For operation, refer to Section 8-I "Operation of Function Keys".
Displays "—" if "System-Operation", Tenant Service is set to "No."
–
cursor
3 4 5 6 HRD CPY 7
10-I-4
8