Fellowes ESI Evolve Assembly And Operation Instructions Manual page 21

Step #7
Lock slider plate
Prevent VESA mount quick release
Step 1
To prevent the quick release
function, insert the screw to
the back of the VESA mount.
lock screw
Lock features
If desired, the slider mount can be
secured to prevent the slider function.
This will lock a monitor in position.
lock screw
21