stacking components without leaving marks


as we all can see on audiogon, this is not as easy as it first appears. has anyone found a good solution (DIY or commercial) that can go under the feet of a component LONG TERM that can allow it to be safely stacked on another component? something that wont scratch or discolor the bottom component?
ratso1
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Paper works. I assume that you are going to use stock rubber feet. I stock components too, but I use different feet under each component; the difference in sound when using good feet is quite big.
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