4Pcs Aluminium Speaker Spike Pad with Steel Ball Damping Isolation Stand Feet Nail. Accept weight up to: 200Kg(4pcs). Material: Aluminium Alloy + Steel Ball. Use 3 stainless steel balls and magnalium alloy which has high hardness and density, low harmonic vibration point, and high damping, make their different properties integrated to eliminate vibration and noise better.
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