[Comprehensive Tool]This plotter engineering ruler includes 8 scales and is matachable with all VFR aviation charts.It allows for easy conversion between nautical miles and statute miles [Accurate Measurements]The tool enables you to accurately measure the heading line,draw the expected flight route,solve the problem of deviating from the course,and determine round-trip bearings [Versatile Functionality]It features a sectional side and chart side,a nautical face and statue face.It also allows you to draw north lines and north lines,establishing flight plan checkpoint [Easy-to-Read Design]The opaque white background makes it easier to read scales.The top/bottom scales of regulations and nautical scales are clearly marked for convenience [Product Specifications]Made of durable pp material with for dimensions of 20cm/7.87inch.Each package includes 1 set, Weight: 0.02645547144 pounds, Manufacturer: ALCXAZS