The 8x8 non repro grid is printed on a 3 mil double matte polyester drafting film. The film is sturdy, dimensionally stable, tear resistant, and unaffected by temperature or humidity. It has excellent transparency, flatness, and the matte coated is suited for ink and pencil. Ink lines can be removed with most erasers, pencil lines can be erased many times without line ghosting. Polyester drafting film is suited for mapping, architectural, automotive, engineering, construction, working drawings, archival prints, diazo originals, or any drawing where a sturdy long lasting medium is required.