A black double-breasted coat does the work a gentleman wants from outerwear: it creates a line before any accessory or fragrance has to announce itself.
Current-favorite note supplied by the editor. The Oakmoss & Ivy has no stated sponsorship or affiliate relationship. Product specifications should be confirmed on the live listing.
The editor's current favorite is the black COOFANDY double-breasted pea-coat/trench linked below. The attraction is architectural: a dark, ordered front, a strong collar line, and enough formality to lift otherwise simple clothes.
For an office arrival, let the coat sit over charcoal trousers, a fine-gauge merino crewneck, and dark brown or black leather shoes. For a winter evening, place it over a black roll-neck with tailored trousers and choose a warm, mossy fragrance. For a weekend, keep the palette nearly monochrome but change the texture with dark denim and matte leather boots.
The important fit check is the coat with the layers you will actually wear. The shoulders should remain clean, the double-breasted front should close without strain, and the sleeve should cover the shirt cuff while stopping short of the hand. Because retail listings can change, verify the current fabric, sizing chart, and care instructions on the product page before buying.