How Are the Thule TracRac SR Base Rails Mounted

Expert Reply:

The base rails on the Thule TracRac SR # TH43002XT-508 install via the stake pockets with a bolt, rubber block and t-plate. This hardware included with the Base Rails # TH21508, and if you check out the video that I've included linked to this answer it gives you a decent idea of how everything mounts. You'll want to forward to around the 6:15 mark in the video where Ryan talks about the installation of the rails.

I've also linked both sets of instructions for the TracRac SR that you can reference during installation.