This separator splitts your 33,5mm x 33,5 mm IKEA boxes, eg. the Expedit shelf into 3 sections. I could be used either horizontal or vertical. The label "Dingfabrik" features the Cologne FabLab. Visit the FabLab at http://dingfabrik.deHINT: This separatur just a design with hopefully correct measurements.Designed for 4mm plywood. Other strength than 4mm will need little modifications.Just cut modul A four times and modul B two times. Assemble to a box and place it into one Expedit shelf space. You will need no glue or screws but outside of the Expedit space it will fall apart by itself.