The 15 milmil range by is made exclusively of Merino wool fibers that reach 15 micron. Merino wool is only defined as superfine if its fibers show a fineness of under 19.5 micron. This is why a selection reaching 15 micron is extremely rare and may only be compared to the very best varieties of cashmere. Having a diameter of only 15 microns is an ideal cloth for a suit. In a dark blue Prince of Wales weave, this extraordinary fabric is ideal for two or three- piece suiting, jacketing and trousers.