The Pakkon bento boxes come with an airtight plastic lid which prevents food from leaking out of the container and staining your other possessions.Its slim design makes it effortless to carry in your bag to school, work, or wherever.They are stackable so that u can easily store them.The lunch boxes are BPA free, dishwasher safe, freezer safe and microwave safe.They are designed with your convenience in mind! The containers arrive in a pack of 20, so even you accidentally leave behind a box, they are cheap enough to be replaced quickly