I went up and read the last few posts. Let me update it a bit. I found that rubber bumpers are not the best answer to keep the faces separated. The better solution is using small pieces of Velcro, either the hook side or loop side, doesn't matter. I have used both the sticky back Velcro and the glued back Velcro, set down with ca. The Velcro separates the donut facings about 1/16" which is fine. When installing the rubber band I squeeze the facings and Velcro separator firmly. Works great....