The Tupperware Steamer consists of one cover and two stacking steamer baskets for cooking multiple foods at the same time. Comes with a water level indicator and ridged steaming surface. The surface design helps reduce sticking. Maintain the water level at the indicator as much as possible. In case of evaporation refill with hot water. If water is boiling vigorously, lower the flame to prevent water from bubbling over into the food surface. Smart venting hole placement for even cooking throughout Smart design ensures condensed water moves to the sides of the dome rather than drip on the food.