The Ultra+Latch 5.2 Cup Square food storage containers feature a domed
locking lid with air-tight leak-proof silicone gasket seals, to keep food fresh
longer. The Brite Green color-coded matching system makes it easier to find
the correct lid and base combination. Containers stack neatly in use and nest
efficiently in storage. Ultra Latch containers are freezer, microwave & dishwasher
safe, as well as BPA-free and phthalate free.