L-Acoustics A10 Owner's Manual page 95

Rigging procedures
2. On each K2-JACK foot, rotate the wheel counter-clockwise until the central part is close to the base.
3. Attach the feet to the bar.
Insert the feet at both ends of the bar. Pivot the central part so that it
comes in contact with the bar.
Lock the feet in position by giving
a quarter-turn to the locking system.
A10 owner's manual (EN) version 1.1 95