Durable crystal clear Tritan plastic bases are shatterproof and resist stains and odors;Updated lid design is easier to clean and dry, and helps prevent overfill spills;Premier Easy Find Lids snap to bottom of container and to each other; bases nest inside each other for organization;One lid fits multiple bases for quick storing needs;Bases and lids are BPA free as well as microwave, freezer and dishwasher safe