National Geographic TOPO! Expansion Pack U.S. Streets 3D Map CD-ROM (Windows) Requires TOPO! State Series Mapping CD-ROMs (Windows Version, sold separately) 3D - Views and Animated Fly-Thru allow you to visual the lay of the land Updated Streets &amp; Roads provides the detailed road data available GPS USB Support provides the latest connectivity to the newst GPS receivers Live Map Update ensures you always have the most current maps and software