Valve Cover Gasket question

You want the DCC-5249581AB ones. Steel core with rubber. I use them on my 360. No leaks, and I have reused them so many times I have lost count. The other ones are are really stiff, and may not be reusable at all. I have them as well, but have never put them on, they feel much stiffer than cork material. The steel core ones have a soft rubber material, and the steel core is what keeps them stiff. The rubber on them also has sort of a double seal on each side. Great design.