These compostable clear 16oz salad bowls are made from PLA, (polymer made from plants). They are suitable for cold foods, freezer safe. Not microwavable. PLA products should be stored in a cool place below 110° F and out of direct sunlight. These are certified compostable in a commercial facility, which may not exist in your area. Bowl dimensions: 5.4" top diameter x 2.7" tall.