Box dividers. Pack of 50 pieces. 81 Cell Assembled Set for 1 oz (30ml) Boston Round. Cell Size: 1.25" x 1.25" x 4". Thickness: .024pt Chipboard. Designed to fit inside any 12 x 12 box. It perfectly fits the large 12 x 12 flat rate USPS box. Ideal for e-liquid juice vapor cigarettes, essential oils, cosmetics bottles. Made in the USA.