My nails are thin and break easily. That is why I purchased the Daiso Nail Hardener, the ultimate value-for-money, practical product. When I apply the nail hardener, my nails gain a shine and become smooth. A transparent protective layer forms on the nails, making them feel stronger. The scent is similar to nail polish, so perhaps because I am used to it, I don't find it off-putting. Since the nail hardener looks pretty like clear nail polish and helps strengthen my nails, it is like killing two birds with one stone.