Factual error: Tuco Salamanca's gun is a Taurus Raging Judge. Season 1 - as well as Season 2 - where Tuco's gun is prominently featured, are set in 2002. The Taurus Judge series wasn't produced until 2006.
Factual error: While Jimmy is climbing up the billboard to save the worker, some buildings can be seen in the background such as the TriCore Labs, Embassy Suites Hotel, and the Bernalillo County Metro Court House. This episode is set in 2002 but the Embassy Suites and TriCore Lab buildings weren't built until 2004 and 2005 while Metro Court was still under construction at this time. Even the billboard tower in this scene didn't exist until years after it was set.
Factual error: The intro scene for this episode shows Mike getting off the Rail Runner Express. This train didn't come into service until 2005. This scene is set in 2002.
Factual error: When Mike is waiting in the parking garage with Sobchak for Pryce to arrive, the AT&T logo is prominently displayed on an office building in the background. This logo is the new style introduced in late 2005 and didn't exist in 2002 when the show is set. (00:11:25)
Factual error: In one of the shots shown of Chicago, the Trump Tower can be seen on the right. Although the episode is set in 2002, this building did not exist until the late 2000s. (00:28:33)
Answer: It might be the Panavision cap he wore when directing his terrible commercials.