I have a group of eight J.A. Michell Tenderfeet isolation cones. These can be used under any item of audio equipment. They are milled from aluminum, which is then anodized to reduce discoloration or tarnishing. The cones are in excellent condition with hardly any signs of wear. I will sell them in sets of four at $25/set, shipping by USPS priority included in the U.S. lower 48.
