If your GPS or cell phone runs out of power, depend on the BRUNTON® O.S.S. 20B compass to get you where you need to go. This reliable, no-frills navigation tool displays your heading with 2-degree resolution and includes an inch and millimeter ruler along the side. The O.S.S. system with Eclipse circle-over-circle alignment has a tool-free declination adjustment to keep you firmly on track.
O.S.S. Eclipse circle-over-circle alignment system