Men's Henley (Polos & T-Shirts)

Take a collarless knit top, cut a short opening at the throat, and add a strip of fabric carrying two to four buttons. That strip is the placket, and it usually runs four to six inches down the chest. Rowers at Henley on the Thames wore the style, which is where the name comes from.

How the placket is built decides whether the shirt survives. A proper one uses a separate piece of fabric with interfacing, a stiffening layer sewn inside. So the buttons have something firm to pull against. A cheap one folds the jersey over on itself and the buttonholes stretch into slots within a season. Waffle knit, a thermal fabric with raised squares that trap air, is the common cold-weather version and adds real warmth for very little weight.

Against a crew tee, the henley trades a fixed closed neck for a control you can change at lunchtime: open two buttons and it vents, close them and it covers. Against a piqué polo, it gives up the collar, which is exactly what keeps it out of business casual and inside the weekend. A v-neck tee opens the same triangle of chest but fixes it permanently open.

Layering under a flannel shirt, a chore coat or an unstructured jacket is where it looks best, because the placket puts interest at the neck where the jacket frames it. Cold weather in waffle knit is the other clear case. Offices that require a collar rule it out, and so does a very short neck, since a placket sitting high draws attention to the throat and shortens it further.

Press your thumb against the placket before buying; you should feel a firm layer inside, not two thicknesses of soft knit. Buttons should be flat and small, around a quarter inch, because large ones drag the opening crooked. Wear it with one or two undone, since fully buttoned it reads stiff. Undo them all before washing so the placket does not twist as it dries.