I have a license plate from the Heliongijang province. I would like to know what is the last character in this image and how is it pronounced. Also, I have seen many license plates which have this character in the end. So, I would also like to know is this a character that represents the city or is it something else?
挂车 seems to mean a "trailer". Searching for "挂车号牌" brings up images of trailers, most of which have number plates that end in "挂" (see below). My Chinese is not that great but according to this document (page 15, item 5.10), trailer number plates are distinguished using the character "挂".