Lids snap to the bottoms of the container bases and to each other, so you can always find the right lid. One lid fits multiple bases. Different sizes to meet all of your normal food storage needs. Containers nest for compact storage. Square shapes take less refrigerator space. These food storage containers have thick container walls durable enough for everyday use. Super-clarified bases make it easy to see what’s inside. Plastic food containers are microwaveable, freezer-safe, dishwasher-safe, and BPA-free. Made in the USA.