Presto® 09903 Pressure Cooker Sealing Ring with Automatic Air VentThe sealing ring fits around the inside rim of the cover and forms a pressure tight seal between the cover and the body of the pressure cooker during cooking or canning. When installing a sealing ring, work it into the cover in four small sections, for example, top, bottom, left and right. Work it into the groove a small section at a time until it is fully in place. Place the cover on the cooker body. Put one hand on the top center of the cover and