The red underfelt acts as a universal joint allowing the white felt to move about to find the best position for muting. The red felt is soft and very flexible. It is a true felt not a woven cloth. If the red felt is glued onto the damper block by putting the glue on the block first then the white felt glued onto the red felt by putting the glue on the white felt the flexibility of the red felt is the greatest possible. Newton
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