4.0 Cup Ultra Seal Square Food Storage Container(5) Sterilite 03314706 4.0 Cup Ultra Seal Square Food Storage Containers , 6.7" x 6.7" x 2.5", Ultra-Seal 4.0 Cup Square food storage containers have a blue color-coded matching system to help find the correct lid and base combination without rummaging through the cupboards. The gasket and four latches in the lid create an airtight and watertight seal that keep food fresh and prevents liquids from leaking. A vent in the lid releases steam when the container is placed in the microwave, and all containers store efficiently both when in use and when not in use. Ultra-Seal containers are freezer, microwave and dishwasher safe, as well as BPA free and phthalates free.4.0 Cup Ultra Seal Square Food Storage Container