<P> The most common plates are embossed black - on - white to indicate state ownership; plates indicating KPA use are white - on - black . Motorcycle plates are black - on - yellow or black - on - orange . The very few privately owned motor vehicles which exist in North Korea bear black - on - red plates, while diplomatic plates are white - on - blue . Other types of vehicles (trolleys, emergency vehicles, buses / taxis) are indicated with additional numerical prefixes . </P> <P> In South Korea, 6 types of registration number plates (3 variations of size, both non-commercial and commercial) are issued currently . Prior to 2006, sizes of plates were 335 by 155 mm (13.2 by 6.1 in) for normal vehicles and 440 by 200 mm (17.3 by 7.9 in) for large vehicles (buses with length over 6 metres (19 feet 8 inches) and trucks with payload over 4 t (3.9 long tons; 4.4 short tons)). Since November 2006, standard plate size for normal vehicles was changed to 520 by 110 mm (20.5 by 4.3 in), resembling European Union standard . Nonetheless, older 335 mm (13.2 in) plates are still effective for older vehicles and some models not fit for new standard, which are mostly imported cars . One example is Ford Mustang . Even cars with 520 mm (20.5 in) plate in front and 335 mm (13.2 in) plate in rear are not rare . </P> <P> Non-commercial vehicles (nationwide registration number "00 - X-0000": X is one Hangeul character denoting type of vehicle) bear plates with white background and black letters, while commercial vehicles (Region name is added as prefix like "Seoul 12 GA 3456") with yellow background and black letters . In older system, non-commercial vehicles plates had green background and white letters . </P> <P> There are a few exceptions, including diplomats and United States military . </P>

When did nj stop using blue license plates