Vintage Brooks Brothers miUSA tweed 3/2 sportcoat (estimated 46S: 24" pit to pit, 24" sleeve, 32" length).
Intentionally oversized fit (tts 40L) to get both natural drape and the roping (bump) on the shoulders.
Beautiful jacket and a perfect representation of ivy style. BB has remade it as the "#1 Sack Sport Coat", with the fabric changing every season.