DeLorme Earthmate 2010 GPS LT-40 Features - Includes Earthmate GPS LT-40 device and Street Atlas 2010 software; device attaches to your computer's USB port Voice-guided navigation and optional voice commands help you navigate without needing to view your computer screen Optional 3D viewing perspective while GPS tracking helps you better track your position Automatic back-on-track routing helps you get back to your preplanned route after making a detour