Protractor compass
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The protractor compass is a type of compass commonly often used in hill walking, orienteering and other outdoor sports and pursuits.
Named after the protractor, a protractor compass consists of a baseplate, with an inscribed direction-of-travel arrow, and a rotating housing marked out in degrees, containing a magnetised compass needle. This allows bearings to be taken directly from the map, adjusted for magnetic declination, or recorded numerically and re-used.
For usage, see Compass: Using a compass.
