2.2.6 Basics/The design/Basic elements The grid The basis for our design Our design grid consists of square units.What makes it unique is the fact that these units do not have fixed sizes. Their sizes change in proportion to the respective format. As a result, the grid will always be 30 x 42 units for all DIN portrait formats. DIN A US letter 42 U 42 U 1U = 7mm: Example DIN A4 Unit widths for standard formats DIN A5/DIN long 5mm/0.20inch DIN A4 7mm/0.28inch DIN A3 10mm/0.39inch 32 U DIN A2 14mm/0.55inch DIN A1 20mm/0.79inch 30 U DIN A0 28mm/1.10inches US Letter 6.65mm/0.26inch 30