We've had so many shakers with tiny "corks" or plastic stoppers in the bottom. They invariably leak, and eventually fail. Most shakers are opaque, so you don't know they need refilling until they don't work. These shakers make sense. You can SEE through the glass at the bottom of the shaker, so you know when you're running out of salt or pepper. And you do not need to turn the shakers upside down to refill them. They look good, and they work well.