Martin Audio MLA User Manual page 409

MLA System
USER GUIDE
Are NOT SAFE and MUST be re-seated until the centre button pops out.
Next remove the flying pin stowing the rear bracket on the MLA and swing it out of the cabinet and into position on the grid.
There is a small tongue on the rear bar to assist swinging it out of the stowed position;-
Align the holes in the rear bracket with the corresponding holes in the flying grid and pin them in place;-
MLA System User Guide V2.1
409