Need recommendations for floor spike protectors

Thanks for the great post ghosthouse .
 If "herbie" says its so , it is so.
His advice is good as gold .

Thanks for all the responses.   A gentleman from revel responded with, well, interesting advice. Go to Home Depot and get furniture sliders.   Not doing that...

i sent an an inquiry off to herbies, are they usually good at responding?  Been a few days.  

Another Herbie's glider user here (in brass).  Great product and so reasonably priced.  I've been using them for several years with my DeVore Super 8's on carpeted flooring.  Really makes it easy to dial-in your speaker set up.