Panasonic KX-T336 System Reference Manual page 66

2.03 Stacking on the Basic Shelf
1)
Expansion
shelf
Basic shelf
2)
Screws
Note :
If the system is to be expanded to 3-Shelf System, proceed to Section 2-B-3.00
"Expansion to 3-Shelf System."
• To connect the expansion shelf with basic shelf,
place the holes of the expansion shelf exactly
on the holes of the basic shelf.
• When the holes are placed properly, fix them
with the three screws immediately to prevent
the expansion shelf from falling down.
2-B-10