I recently purchased a Patek Calatrava 3426. I can’t find much information.

I'm trying to figure out the lug width before I have the watch to measure it. I ordered an 18mm strap, but I now see an Ai prompt that it's a 19mm strap. It's confusing because there are so many variations. This is a three piece case. Even the case size varies, some list it as 33mm, some 32mm. There is little information online about many Patek models, unless I don't know where to go? Does anyone have any idea what lug width this watch has?