I used some pipe insulation on a 3/4" bar across the rear side window of my work van ...to secure a small buddy step-ladder in place with a bungy cord.   Over the years the pipe insulation has shed some of its innards and is now stuck to the pipe.   I bought a couple of pool noodles a few months ago for filler insulation in between the top of a sliding door and the ceiling framework in my lounge room....however it was slightly to big.
So now I will use a section of pool noodle to see if it works in my van to hold the step ladder in place.   

  Anti-vibration and security.