Here’s what you get when middle-aged dads get on Snapchat . . .

43-year-old Brian Slocum is a single dad in Sarasota, Florida.  And his nephew recently introduced him to Snapchat.

Then on Tuesday, Brian was driving past a pawn shop . . . and thought it would be funny to go in and pretend he wanted to SELL his seven-month-old son.

He put him up on the counter in his car seat . . . told the owner he was “barely used” . . . asked what he was worth . . . and secretly recorded it all on his phone.

His big mistake was he never told the store owner it was a joke, and just walked out.  So the guy called the police.  Then a few hours later, Brian saw the story on the local news and freaked out.

He called the cops to try to explain what happened.  Then DOZENS of officers showed up at his house.  But they ultimately decided not to charge him with a crime.

Brian talked to the local news later on and said his son is the most important thing in his life.  And he understands now that pretending to sell him at a pawn shop wasn’t a great idea.