The Grenfell trench coat is a garment so steeped in history you can see it. A favourite of both British and Commonwealth armed forces, the Windsor is the quintessential trench coat for an autumnal day, with belted cuffs, epaulets and storm flap all present and correct. For a luxury trench that harks back to Roaring Twenties excess, try the Mayfair; a seamless combination of Grenfell Cloth and Merino Wool.