With its built-in rubberized seal and four locking tabs Lock-its provides an extra secure lid for your food storage needs. Lock-its will also stay organized with the Easy Find lids system: Lids snap to bases and other lids. You will never lose a lid again! One lid fits multiple bases and the various sizes nest for compact storage. Lock-its are safe to use in the microwave, freezer, and dishwasher and are available in ten sizes. features:& Bull; 9 Cup square food-storage container with clear polypropylene base; lid provides 4 locking tabs and molded gasket for spill-proof use; pieces snap together and nest with other Lock-its containers (Sold separately)• safe for use in the microwave, freezer, refrigerator, and dishwasher material: rubber and polypropylene instructions: dishwasher-safe dimensions: 9.88″ x 19.31″ x 7.25″.