The Round Ruyao Fair Cup is the secondary vessel used in many style of Gongfu tea. It is essentially a small, open vessel. When the tea has been steeped to the desired concentration in the primary vessel (gaiwan, teapot, etc.), it is dispensed into the fair cup before serving to ensure that everyone receives tea of equal strength. Put a tea strainer on the fair cup, it can prevent the tea leaves that from the teapot come into the fair cup.