L-Acoustics X12 Owner's Manual page 63

Rigging procedures
3. Rotate the X-BAR until perpendicular to the front grill.
Use the screws as reference points.
4. Tighten the X-BAR.
a) Lift the lever and rotate it counter-clockwise, release the lever and rotate it clockwise.
Repeat until the X-BAR is tightly secured.
X12 owner's manual (EN) version 1.0 63