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A powerful navigation tool, the Lowrance Endura Sierra GPS is preloaded with premium outdoor content to provide a complete, out-of-the-box experience. Comes with richly detailed topographic map pre-installed and ready for immediate use—no need to purchase or download! Digital, stabilized 3-axis compass and barometric altimeter provide added navigational aid. Simple touch screen interface and physical hot key buttons offer ease of use and quick access to the unit's main features. High-performance processor and fast memory provide quick map redraw and panning capability. Large, full-color QVGA screen offers easy viewing. Preloaded map features Intermap Accuterra™ high-resolution topographic maps, extensive outdoor trail networks and points of interest. Also features NAVTEQ® road network for the contiguous 48 states and an upgrade option for full-featured, turn-by-turn navigation. Besides the preloaded mapping content, a large range of map options are available via web download or on preloaded MicroSD cards (sold separately). MicroSD card slot accepts cards up to 32GB to augment 4GB internal memory. Trip computer records trails, trip times and distances. Multimedia functions include MP3, voice notes, picture viewer and video player. Lowrance Endura Sierra can be customized with public domain and community-based content like GPX trails, general outdoor points of interest and up to 3,000 geocache locations. Power standby mode saves battery life and offers fast startup. Features a speaker, headphone jack, microphone and mini USB port. Waterproof construction is rated IPX7 to withstand immersion in 1m of water for up to 30 min.