The result? A "solid" feel that golfers described as "soft but pure." It was a craft that couldn't be replicated by a machine alone; it required the eyes and ears of a craftsman who could tell if the steel was ready just by the color of the glow and the sound of the hammer. The Runner’s Rhythm

While other manufacturers began moving toward "investment casting" (pouring molten metal into molds because it was cheaper and faster), Mizuno doubled down on . In their legendary forge in Hiroshima, master craftsmen (known as Meisters ) would take a single billet of mild carbon steel and stretch it, ensuring the "grain" of the metal remained continuous from the neck to the toe.

The "Made in Japan" collections are still lasted for 24 hours (most mass-produced shoes are lasted for only minutes) to ensure the shape never falters. The Meaning of the Craft

As the company expanded into golf, the Mizuno family looked toward the heritage of their homeland. They realized that the same techniques used to forge —the folding and hammering of steel to remove impurities—could be applied to golf irons.