IT Chapter Two director Andy Muschietti clearly knows his Stephen King: there are references to other King properties peppered throughout Muschietti's 2019 film. Some IT Chapter Two Easter eggs are easy to spot; others, like the carpet pattern from Stanley Kubrick's The Shining, are more obscure. And others still - like that turtle in that classroom when Ben goes back to his old school - might only catch the eye of the most devoted King fans.
One of the most visually striking elements of Stanley Kubrick's The Shining is the carpet in the upstairs hallway of the Overlook Hotel - a pattern that has been referenced repeatedly in pop culture in the decades since. The David Hicks-designed pattern makes a subtle appearance in IT Chapter Two: there's a faded version of it on the bottom of Dean's skateboard.
Actor Brandon Crane played the young version of Ben Hanscom in the 1990 It miniseries. In IT Chapter Two, Crane makes a cameo as a client arguing with adult Ben Hanscom (played by Jay Ryan) about an architecture project.
When Beverly gets trapped in the bathroom stall, we see a bunch of graffiti covering the walls. One of the scribbles reads "Gretta Keene is a b*tch" - something Eddie Kaspbrak would probably agree with, since she's the one who wrote "Loser" on his cast.
Secondhand Rose, Secondhand Clothes makes an appearance in the 2019 adaptation. In both the book and film, it’s the store where Bill finds and re-buys his old bike, Silver. The store is featured in nearly every King story in which Derry pops up, including Insomnia and 11/22/63.