Product review (1 stars): Causes violent shaking.  Forty-dollar sham.
Not only did this product NOT work, but it had the adverse effect of AMPLIFYING the noise and vibration associated with my washing machine.  I installed these feet on a top-loading washing machine in our 1st-floor laundry to help silence the noise and vibration that occurred in the house during use.  With these feet on during the spin cycle, the washer shook so violently that I thought it would come apart.  It rocked so hard that I was afraid it would hit the wall and damage the drywall.  I stopped the cycle and re-arranged the load, because I feared the load was imbalanced.  It was not, but I tried it again anyways.  Same result.  These feet caused a normally-operating washing machine to turn into a rocking, bucking, monster.  I did not even finish the first laundry load I tried them out on.  I slid the feet off and finished without them.  I guess it is better to live with the moderate noise we have now, rather than try anything like Silent Feet again.