It Chapter 2: 15 Insane Hidden Details You Definitely Missed
10. Stephen King's Cup
There are a number of cameos in the sequel, starting with Peter Bogdanovich playing himself right at the start through to Andy Muschietti appearing in the background of the pharmacy scene. But by far the most talked about is inevitably Stephen King's appearance as an antiques dealer who sells Bill his childhood bike back.
The cameo sticks out like a sore thumb, so that's not the interesting hidden detail here - it's his drink. Because the point seems to be to make him seem slightly creepy as misdirection, King is given a tiny cup to sip out of with a straw. And it's the cup that's the interesting detail.
As a nod to director Andy Muschietti - who is Argentinian - King is shown drinking yerba mate (a type of Argentinian tea) out of a mate (the traditional urn-like cup) emblazoned with the Independiente crest. That's the team Muschietti supports from his homeland and the mate was given to him by a fan.