I use Iris 30qt/28 L storage boxes. They measure 16 3/4" x 22 7/8" x 6 7/8". They have completed flat sides and bottoms, with rounded corners, so there are no creases or crevices (very easy to clean). And, they are made in the U.S.A :fullauto: . Plus Iris rarely changes or discontinues their box sizes. Hope this helps.