It's the pin you receive after eating a girl out so good that she morphs into Optimus Prime.
Shaun's Roommate's Friends: So is it just me? Or was Shaun eating out Optimus Prime last Night? Because I found this Mechanical Wings pin on the counter.
Shaun's Roomate: Bro. No yeah. Bro. It was a Woman. He Giant Debbed her so good, that she morphed into Optimus Prime. Her voice got all deep and she got way strong. Then then she turned into a freightliner and then she left.
Shaun's Roommate's Friend: Is his tongue made of the AllSpark? Because if so, I need to find a place to sit.