NauticalMart Pocket Compass Keychain Great compass to keep in your pocket for nautical marine use, or for hiking Made from solid brass, this pocket compass key chain is both beautiful and functional A fully functional nautical marine directional pocket compass keychain Overall Length: 4.75 Inches Chain Length: 1.5 inch Manufactured By Medieval Epic Description Brand new magnetic compass at sea is mainly used for steering a course. The compass reading must be accurate, especially on long sea passages, because an error of one or two degrees in a long course can make a difference of thousands of nautical miles in reaching your destination after many days. The ability to navigate with map and compass is a crucial skill, one that can literally save your life. Your compass and map can also do other helpful tasks like telling you where you are, what’s around you and the best way to get where you want to go.