... 2, Suitable for large and small size vehicles;3, All Caravan/Trailer Connection Cables are Optional;4 ... DVR / 5-Video frequency input for truck Survennice CCTV System display; GPS and 3G is optional on this SystemSIZE7 ... Machnism9V-40V Wide Voltage Input Screen is Optional 3.5", 4.3", 6", 7", 9" and 10.1" ... for 1st year, free repairment for the other 3 years. Whole life free repairment for just equipment ...