Material: Made of high quality, good scratch, stain and odor resistance. Dishwasher, freezer and sterilizer safe. Portable Design: Four separate sections can be stacked in any order. The containers are transparent so you can easily see what's inside. Detachable carry handle for your convenience. Closure system: Twist and Lock system connects jars of any size in any order, a quarter turn locks them together. Stackable: interlocking containers for powders, vitamins, supplements, and snacks. Detachable carrying handle: for easy carrying or attaching to the bag; stackable fits in shaker bottles for transport.