The threaded lids are simple and easy to operate, and provide peace of mind against spillage. When not in use each container collapses to a minimal height, taking up significantly less space in your bag. Available in four different sizes, the X-Seal & Go containers are perfect for culinary adventures on the trail, as well as taking a lunch to the office. Durable and easy to care for, made with the highest quality food-grade materials, and microwave and dishwasher-safe