The bearings at the bottom of my kitchen chairs constantly get clogged by the tumbling tumbleweeds. No, I am not talking about desert cactus. I am referring to shedding hair of one large St. Bernard. Hubby tried to contact the store where we purchased the set, but it had long gone out of business. Then he called around and learned that the manufacturer had also gone out of business. His last resort was searching replacement parts on the internet. I personally think the industrial bearings he ordered were a bit overkill.