Lids snap together and to container bases so you can always find the right lid. Graduated sized containers nest for compact storage. One lid fits multiple bases. Square shape for optimal space utilization. Super-clarified base to easily see contents. Microwave, feezer, and dishwasher safe. Thick, durable container walls for everyday use. Bases and lids are BPA free. Sets include: (3) .5 cup, (2) 1.25 cup, (1) 2 cup, (2) 3 cup, and (1) 5 cup containers.