Standard plate sizes for large format cameras in the UK and USA start at 5 x 4, progress through 7 by 5 and, for most people, end at 10 x 8. Each box holds 20 plates and there is an indication on the side of the order in which they are stored. This will assist indexing if you want to put a label on the front of the box. These boxes are designed to hold plates of these sizes and no more than 2.5 mm thick. Each plate is separated by 1.5 mm. The boxes should be sturdy enough to prevent any plates rubbing against each other, and the overall height of the box is less than the length of the plate so that the plate can be extracted by holding it on the sides to lift it clear. I welcome any feedback from makers or users to improve the design.