6 months & up. Six graduated, numbered cups are great to use for stacking, nesting, sorting and water play. Each cup is numbered from 1 to 6 on the bottom and is volumetrically accurate. Fill cups 1 and 2, for example, and it will equal the volume of cup 3.They teach basic counting and math concepts. Made from recycled milk containers and made in the USA. Dishwasher safe. Colors may vary.