Designed for use with topographical and radio navigation charts this plotter is simple, versatile and multi-functional. Manufactured in clear flexible plastic with white scales it measures 205mm x 65mm. Magnetic or true headings are simultaneously obtained from the compass rose by simply aligning horizontal centre line with desired track. With 1:500,000 scale to 50nm. And outside edge printed on each side with conventional protractor degrees the RNP-1 also incorporates scale 1:250,000 nm to 25 nm . Also available as above with scale 1:500,000 nm and 1: 100,000,nm please write if you require this item in the delivery comments.