This was bought to be used for filling up unused slots in the 500 series midas box. It fits the box perfectly closing up those unused slots for you. It is of string build and I would definately recommend to people.
However, I did have one slight problem with this which is the only reson I didnt give is 5 stars. Since these are to match with the Midas 500 series lunchbox you would image they would be the same color blue that he Midas lunchbox is. They are a slightly different shade of blue than the lunchbox, but they do the job they are supposed to perfectly.