For explorers and search-and-rescue professionals, Silva's Expedition series has been the longtime global leader in compass accuracy, precision and durability.  This €œfull-size€ base plate compass for experienced navigators contains everything you need in a compass and has added functionality for GPS. € Compass housing made from Dryflex„ - rounded base plate - comfortable and fits any hand size € Patented red/black orienting lines - easy and €œfool proof€ to take bearings € Map measuring scales mm, inch Romer scales, 1:25k, 1:40k, 1:50k - compatible with basically any map. € Luminous markings - enables night navigation € Friction feet - increases precision in map work € Hole for marking positions on map with pen/pencil - increasing precision € Built in magnifier for detailed map reading