The original Silva Field Compass has base plate map-measuring in mm and scales of 1:50,000 and 1:25,000 compatible with most maps. __ It has a  DryFlex rubber bezel for improved comfort and grip, and a detachable safety-release lanyard. __ Being so light and compact means the Field Compass is an excellent choice for keeping in your pack in case you need a quick bearings check, so is ideal for weekend walks or for use on Duke of Edinburgh expeditions.__ For route planning or more serious navigation use, consider getting a longer-baseplate model.