Made from Borosilicate Glass, thanks to its soft silicone seal, this container is airtight and leakproof. Skilfully engineered for use in the microwave, the lid utilises a clever air vent designed to release steam once food has been reheated. This means that food can go from freezer/fridge/pantry straight into the microwave for reheating. No mess, no fuss. With its airtight design, this product is also perfect for picnics and bulk cooking. The colour coded lids and bases, which fit all sizes in the range of that colour, make finding the right lid a breeze.