What is "retractables"

Usage examples of "retractables".

And as theories go this was all very fine and pleasant until Veet Voojagig suddenly claimed to have found this planet, and to have worked there for a while driving a limousine for a family of cheap green retractables, whereupon he was taken away, locked up, wrote a book, and was finally sent into tax exile, which is the usual fate reserved for those who are determined to make a fool of themselves in public.