APRís DCPP-5 Deluxe Douglas International Navigation Combination Protractor and Parallel Rule Plotter has additional advantages for pilots and seamen as well.
The DCPP-5 is designed with high visibility color graphics, a tinted grid, and larger numbers and lines for easier positioning and reading. This plotter eliminates the need to use dividers and parallel rulers. A hole in the center of the instrument is used to conveniently mark and rotate the plotter.
Also included are complete operating instructions with examples to lay out a course or bearing, read the course bearing, use as a parallel rule, find departure or latitude between two positions, find magnetic course or bearing from true course, and to plot lines of position.