3.2 megapixel auto-focus digital camera with automatic geotagging and 4x zoom 3-axis tilt-compensated electronic compass and barometric altimeter High-speed USB for faster map and photo transfers with your computer Improved 3" sunlight-readable, color, touchscreen display High-sensitivity GPS receiver with HotFix for improved performance and reception 850 MB of internal memory for map data and photos microSD? card slot for optional mapping and data storage Built-in basemap with DEM (digital elevation model) data Wirelessly share routes, tracks, waypoints and geocaches between units Easy-to-use, touchscreen interface, 400 x 240 pixels (H x W) Waterproof standard: IEC 60529 IPX7 Preloaded U.S.Topo 100K (only on 550t)