Extron electronic Low Profile Floor-Mount Raceway System for A/V Connectivity AVTrac - Manual (Page 13)

Installation
AVTrac • Installation 11
Step 2: Connectivity Box
By this point, the base track, side ramps and end ramps must be securely fastened to the floor.
To attach the connectivity box to the base track, follow these instructions:
Secure connectivity box to the floor
Masonry
Screws
The end of the connectivity
box with three mounting holes
faces back towards the track.
2-1 Reposition the connectivity box, in the correct
orientation, over the pre-drilled holes in the base track
(see instruction 1-6).
The end of the connectivity box that has three mounting holes
faces back towards the track.
Using at least three of the provided 3/16" masonry
screws, secure the box to the track and floor.
Remove all dust with a vacuum cleaner.