I initially was looking for glass containers to store powders in, but didn't want to buy new ones. Like most people, I have a good selection of mason jars however, they're nothing special. I was looking to use what I have but give it a little razzle dazzle. These lids did the trick! My mason jars no longer look so homey, lol. The size I purchased fits only the wide mouth jars. I'm hoping to find ones that fit the standard/regular jars.