1 Set of Four High Quality Isolation Spikes with Pads The purpose of using isolation spikes is to suspend acoustic feedback from your speakers or sub-woofer. They can be installed to separate your turntable, CD player, amplifier or other audio components from vibration. Therefore, the tones be more focused and tighter. And, there be much less noise to be transferred to other rooms from the floor. Application: Set up the spikes beneath the equipment as same as the demonstration. No drill is needed. No adhesive substance is recommended, as it may influence the isolating effect. Colour:Silver Material:Brass white sand Package Contents: 4 x Speaker Spikes 4 x Speakers Amplifier Feet Pad Only the above package content, other products are not included. Note: Light reflection and different displays may cause the color of the item in the picture a little different from the real thing. The measurement allowed error is +/- 1-3cm.