Derwent Drawing Scale DividerAn absolute must have for any artist, the Derwent Scale Divider scales plain or detailed subjects up or down onto paper or canvas. Transfer measurements from photographs, paintings and more with ease onto paper, achieving accurate proportions every time. Reduce or enlarge images in ratios from 4: 1 to 1: 4. Folds down and away and you can easily slip it into your backpack. Pine wood construction.