In some of his early appeareances, Lefty had slightly hidden angry eyebrows, thus giving him a mean look, but the eyebrows were removed in later sketches.
Lefty's boss is the only character who refers to him as "Lefty"; in CTW production materials and Sesame Streetmerchandise, such as storybooks and record albums, he has usually been referred to simply as "The Salesman."
A 2008 book, Storybook ABCs, is the first use of Lefty's name in print. Grover is dressed as Jack (of "Beanstalk" fame), and the Salesman approaches from behind a tree with an offer: "Care for some candy beans for that cow?" Jack replies, "Thanks, Lefty! And do you also have a candlestick?" Lefty apparently has one in stock -- a few pages later, Jack (of "Jack Be Nimble" fame) jumps over the candlestick. At the end of the book, Lefty returns to feed four and twenty blackbirds with birdseed that fills his carry-all bag.