A grommet for a hookah bowl is a small rubber or silicone ring used to create an airtight seal between the bowl and the hookah stem. This seal is essential for proper airflow and optimal smoking experience. Grommets come in various sizes to fit different hookah models and bowl types. When selecting a grommet for your hookah bowl, make sure to choose one that matches the diameter of both the bowl's connection point and the hookah stem to ensure a snug fit and prevent air leaks during your hookah session. If you're unsure about the size you need, many hookah specialty stores or online retailers offer grommet assortments that include different sizes to accommodate various setups.