Click the Buy button to see your price. Consists of a roller mounted on a plotter with distance scales of 1:20,000, 1:40,000 and 1:80,000 to fit N.O.S. Coast and Harbor Charts. Has an inch scale, semicircular protractor and two quarter-circle protractors. Courses and parallel lines are transformed and kept parallel by means of two rollers mounted on a single axis.
