So I need to put back my stock interior and I used the OEM seat rails to mount my Recaro Pole Positions, now I need to mount the OEM seats on the seat rails again.

The problem is not mounting the seat to the rail and the rail to the car, that is easy as, yeah, well, easy.

The problem is what I've marked in the image below.
How the hell do I attach that round thing to the slider?! I see the holes and stuff but I cant make it fit, I have better pics on my mobile phone, I'll try to get them online when I get home but yeah.

I tried for an hour without getting it on but no go! I'd appreciate any help, and I need to get it working pretty damn soon so a speedy answer is greatly appreciated!

 

Bump, anyone?

I found out what it does, it is what makes the seat pull forward when you "quick release" the seat for someone to enter the back.