Green Gizmo I.D.S. (Isolation Damper System) (Black) Comes with 8 I.D.S. units. Viscoelastic material, elegant design made in the U.S.A. Externally generated vibratory energy is prevented from reaching an end structure or component. Energy is dissipated in a vibrating structure or component. Fully customization design; allows you to fine tune your sound to your set up. Great for studio monitors, speakers, DVD/Bluray players, receivers.