This compass features an ergonomically designed base plate, so it fits comfortably in your hand. The extended base plate has inch and 1/10 mile direct reading scales that meet U.S.G.S. standards. 1:24,000 and 1:62,500 direct reading scales ensure accurate mapping and plotting. 2° dial graduations and built-in magnifier help you read map details. Declination scale lets you make quick adjustments of map bearings to field headings.