Near the end of the episode, amidst his monologue, Mike gets out of the car with a single sleeve pulled up. The camera changes angle and, suddenly, both of his sleeves are pulled up.
For the purposes of policing, Philadelphia is broken up into "districts", not "precincts". The word "precinct" is rarely, if ever, used by either police officers or civilians.
Detectives from Philadelphia, while questioning Mike, refer to the west section of Philadelphia as the West Side. In Philadelphia this area is known as West Philly, and is never, ever referred to as the West Side.
The show takes place circa 2002. At the beginning of Five-O Mike gets off of a train from Philadelphia. The train is one of the Rail Runner trains. The NM Rail Runner is a commuter train, and it wasn't in operation until 2006.
This show takes place years before the events of Breaking Bad, but yet Mikes granddaughter Kaylee appears to be the same age in the as she is in breaking bad.