X-gps S550hd 5.0" Hd 800480 GPS Navi+sirfv+128mb Ram+4gb Au/Us Map&radar Detector CPU:SIRF IV Atlas 600MHz CPU GPS module:SIRF ATLAS V SDRAM:128MB SDRAM and Built-in 4GB Flash Display:5.0" TFT 800*480 True Color LCD Touch Screen GPS accuracy:Position - Less than 10 meters (33 feet), 95% typical velocity - 0.1 meters per second steady state