Forgive me, I’m running out of descriptive names for Dean’s plethora of button up shirts. This one is similar to some shirts Dean’s worn in the past (including Dean's Green Bold-Stitching Shirt), but I believe it is a unique shirt. It’s grey with dark buttons. It also has pronounced seams down the front and around the pockets. It has a slightly higher and stiffer collar than Dean’s other shirts.
Brand: Eddie Bauer
Dean wears this shirt in Blade Runners (9x16), from when Crowley calls them for help, until they get Crowley back to the Bunker.
In Twigs & Twine & Tasha Banes (12x20), Dean wears this shirt at the beginning of the episode when he and Sam are in the Bunker worrying about Castiel and Sam gets the call from Alicia and Max.