Hi Radu,
I went through this not too long ago. I believe I actually bought this from the Classic center. It came with a hook at each end. Hans is right, they didn't last long because the rubber band oxidized, like all rubber bands do, and fell apart. Then the clips laid on the carpet until they were sucked up by the vacuum cleaner.
If you don't have the clips, the Classic center MAY have them. If not, they are easy to make. I researched and found UV resistant rubber bands but were black and not the white as original. So what, at least the will last much longer.
If you can't find them, I'll see what I can dig up.
Wallace