Heavyweight clear plastic storage boxes designed to store a ream of SRA3 or A3 paper. Perfect for printers looking for a way to store open reams between print runs. SRA3 is a size up from A3 and is used by printers when running full bleed A3 prints. This versatile storage box is also ideal for photographers looking for large developing trays. The size of this box means you can develop images up to 12" x 16". .