The 'Best By 07 SEP 18 043 / 40' meme features a close-up photo of a printed expiration date on a product package. While it seems like a mundane image, the specific date and numerical code became a staple in the surreal meme community and shitposting circles. It is primarily used as a reaction image to indicate that something—a joke, a person's relevance, or a specific mood—has reached its 'best before' date and is now officially stale. The hyper-specific nature of the 2018 timestamp adds a layer of absurdist humor, making it a favorite for users who want to signal the end of an era or the death of a trend with industrial-style finality.