The Fermentaholics Unbleached Muslin Kombucha Covers are the perfect addition to your fermenting experience. They are designed to ensure your Kombucha stays fresh and beautiful, while also keeping flies at bay. The innovative design allows for a tight weave, which helps maintain the ideal oxygen transfer rate, allowing your Kombucha to breathe and ferment at its best. This set includes four covers, each with a rubber band for easy application and removal. The covers are 10 inches on a side, making them suitable for a wide variety of jar openings. Made from soft, unbleached muslin, they are gentle on your Kombucha and your hands. Simply hand wash them, and they're ready to use again. Enjoy the benefits of a clean and inviting fermenting environment, all while allowing your Kombucha to thrive.