- Men’s cayenne red shirt - Monaco collar, long buttoned sleeves - SLIM fit, pure linen fabric - Buttons to fasten, IKKS button on left cuff - IKKS #actforbetter: fabric contains pure Masters of Linen® and European Flax® certified flax Red alert for THE must-have summer shirt: the pure linen shirt in a gorgeous cayenne colour. Wear against the skin, with chino Bermuda shorts.