Derwent Drawing Scale DividerThe Derwent Scale Divider is an ingenious drawing tool invaluable to artists which allows you to scale your pictures in ratios from 4: 1 to 1: 4. It makes it easy to transfer measurements from life, photographs and sketches ensuring you achieve accurate proportions every time. A traditional tool, it is ideal for helping to achieve the correct perspective in your drawings. It folds nearly away and will slip easily into a backpack when you are out and