Accessory scams.

Legal UK CBs have always carried a stamp mark to show that they are legal to use.
In an attempt to fool the authorities, some people stuck false stamp marks on their illegal CB radios. This usually took the form of a paper sticker which, unless you looked carefully, could look genuine.
Beware of such stickers, check that any approval mark is part of the original marking - not a sticker. Remember that any CB that operates on AM or SSB is illegal in the UK. If such equipment has a stamp, it is not valid.