When I recently pulled my seats out of the Challenger, I found these bolted to the bottom of the driver's seat tracks. This was the previous owner's solution to relocating it further back. They measure 2-7/8". I'm gonna try the seat without them, but will reuse them if I find that I'm too far forward. I have a Tuff wheel going in the car, and I am 5'-11", 190 lbs.