John Smedley's 'Belper' polo is made from extra fine merino wool which the brand says "breathes in warm and cold weather", so it's perfect for wearing all year round. It's knitted in a fine gauge for a lightweight handle, and the slim shape is framed with neatly ribbed trims. The long sleeves up the formality level a touch, so try it in place of a button-down shirt. Shown here with Mr P. overcoat, Mr P. trousers, Common Projects sneakers.