Lock & Lock are the originators of the 100 percent air and liquid tight food storage container concept, with the distinctive snap down locking hinges and silicone seal which allows your food to stay fresh for longer. The four hinged lids have each been tested to open and close more than 3 million times. and the hollow silicone seal in the rim of the lid has superior compression and restoration properties to ensure an airtight seal. Lock & Lock have manufactured these containers with their unique clip locking hinges for securing and opening the lid with ease. Lock & Lock Storage containers have a unique stacking design which can create up to 40 percent more space in your fridge freezer or cupboard. Lock & Lock containers have endless uses around the home, not just for food storage i.e. kid's toys, in the garage, DIY, sewing, first aid, organising drawers, etc, etc. These airtight containers are quite simply the best solution for food storage on the market. Lock & Lock stackable storage containers are microwave, dishwasher and freezer safe.