TWIST LOCK SYSTEMTwist lock system and stackable storage jars4 different size jars from 5 OZ 6 OZ 9 OZ to 11 0Z total 31 OZEach compartment has its own lidLids with silicone ring to ensure 100 leak proof and air tightEasy to twist to lock and unlock PORTABLE DESIGNFour separate sections can be stacked in any orderThe containers are transparent so you can easily view whats insideRemovable carrying handleRemovable carrying handle for your convenience SAFE AND HEALTHY MATERIALMade of premium Eastman TritanBPA and phthalate freegood scratchstains and odor resistanceDishwasherfreezer and steriliser safeTemperature resistance 40 degree celsius to 109 degree celsius Stackable Snack ContainersInterlocking containers for carrying powders vitamins supplements and snacks Removable carry handle for easy carrying or clipping to bag stack fits inside shaker bottles for portability VERSATILE USAGEEasy to store formula milk powder fruit snacks candy nuts chocolate coffee tea food drink vitamins pills small items etc when outdoor activities travel go to office school gym etc