AOpen WT22M-FI Technology Manual page 19

A: install in Wall
B: install to Wall side
C: Screw in A
D Screw in System
E: install to System side
4-2. VESA Assembly
Please use WT22M-FI enclosed VESA screw. M4 length 5mm,
otherwise will be broken system's VESA screw hole.
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