AASTRA 4222 Office for MX-ONE (TSE) User Guide EN - Manual (Page 90)

Installation
Dialog 4220 Lite/Dialog 4222 Office 90
Wall mounting
The phone can be wall mounted without using a special console. Useful
for instance in conference rooms or public areas.
1 Use a screwdriver to remove the handset hook.
2 Turn the hook upside down and insert.
3 Use a screwdriver to remove the two plastic covers.
4 Drill wall holes according to measurements given here.
5 Place screws according to measurements and mount the phone.