DRITZ-Omnigrid Mat Ruler Set. Omnigrid mats have several unique features that quilters appreciate: One side features a medium green background with bright yellow grid lines and the other side features a solid grey without grid lines. Both sides feature a forgiving surface and will not damage your rotary cutter. The grids on these mats feature 1/2 inch markings to the 1/8in and a full surface grid with 45 degree angles as well. This set also contains two of Omnigrid's acrylic rulers: 1x6in and 4x4in. Mat measures 8-7/8x5-7/8in with an 8x5in grid. Imported.