My SDA-1c's have brass cones for feet. I have hardwood style floors. They currently sit on tiny little tiles under each spike. I recently saw somewhere on the web (no I did not bookmark) cups with teflon or some similar material on the bottom. They went under the cones and made sliding the speakers easy for cleaning underneath. Similar to solid brass cups for spikes but with teflon on the bottom. I believe they were called isolators but I can't find them again. Does anyone know what I'm talking about . Help. Please.