remained valid for five years. Issuance of permanent registration plates commenced in 1964. These new plates were made of aluminium and had silver serials on a black background. Serials consisted of two letters and up to four numbers, and were issued sequentially, the first serial being AA100. Certain two-letter series were banned or reserved for government or diplomatic use, while use of the letter V was discontinued after 1971 and, later, Q was not used as the first letter (see Notes/Exceptions below). In November 1986, the plate design officially changed to black serials on a reflectorised white background, following a trial run some weeks earlier. The first official plate of this design had the serial MX100. Silver-on-black plates remain valid and in use, and it is possible to buy a pre-1987 used car with such plates, as vehicle owners in New Zealand do not have to change plates when ownership of a vehicle changes. However, black-on-white plates may be used to replace silver-on-black plates that are irreparably damaged. In September 2022, Kiwi Plates (the only company authorised to produce New Zealand number plates) announced the relaunch of black number plates. After extensive work with Waka Kotahi and the New Zealand Police to ensure the plates were compatible with traffic and toll cameras, the new plates were approved with black backgrounds and an option of silver or white lettering. All new black plates include an 'NZ' hologram to allow officers to confirm validity on the road. The serial font initially remained unchanged following the design change. In mid-1990, a slash was added to the zero character; the first plate to feature a slashed zero had the serial PC10. Plates used sans-serif lettering until the start of the letter codes beginning "DFN" (March 2006), since when plates have used a heavier, partially serifed font, squarer and thicker-lined. The authorities introduced the new font in order to foil attempts to cut out letters and put them back in upside-down when forging license plates. Design Most plates come in rectangular form with all the characters of the serial on a single horizontal line. Plates for motorcycles may split the serial between two horizontal lines, or may be a smaller version of the car plate. Plates on the front mudguards of motorcycles can take the overall form of an arc, although this form is no longer issued. All plates consist of a pressed aluminium plate