I bought a big one for my 14HH Arabian. It was too big BUT it still did its job and didn't fall over. It does not withstand any friction. My horse rubbed against a tree to scratch and tore it open badly. It took 14 or 15 days before the zipper broke, which was half what I expected from the reviews. I just hoped I would have a better experience. Helps keep the horse clean for the show, nothing more. Don't expect it to stand up to prolonged use.