Mizuno is proud to announce the launch of the Mizuno Pro S-4, the newest addition to its growing Signature Series iron lineup and the most forgiving model in the series to date. Developed for players who demand the refined look, precision, and forged feel of a Mizuno Pro iron, the S-4 introduces a higher launching, more forgiving player’s cavity back profile built to expand the performance possibilities within the Signature Series.
The Signature Series was created to serve the evolving needs of the game’s best players. Through years of collaboration with tour professionals and elite ball strikers around the world, Mizuno identified that no single iron profile could fully satisfy the wide range of preferences found at the highest level of the game. Some players seek the ultimate feedback and shot-making precision of a muscle back. Others prefer the added versatility and stability of a player’s cavity. The Signature Series was built to deliver those distinct performance profiles while remaining united by the unmistakable feel, craftsmanship, and precision that define Mizuno Pro.
What began with the Mizuno Pro S-3 established a new direction for Mizuno’s tour-driven iron development, offering a modern player’s cavity back shaped by feedback from the game’s most precise ball strikers. The series then expanded with the Mizuno Pro S-1, a pure muscle back created for players who prioritize ultimate control, workability, and direct feedback.
Now, the Mizuno Pro S-4 adds a new dimension to the Signature Series.
Designed as the most forgiving iron in the lineup, the S-4 was developed for golfers who want the look and control of a player’s iron with added launch, stability, and confidence throughout the set. Its refined cavity back construction helps deliver a more playable profile while preserving the compact, premium appearance expected from Mizuno Pro.
At the heart of the S-4 is a higher launching, more forgiving player’s cavity back design achieved through increased offset, a wider sole, a lower sweet spot height, and a deeper center of gravity. These design elements work together to help players launch the ball more easily, improve stability on off-center strikes, and create more consistent performance throughout the set.
The S-4 also incorporates a progressive design philosophy that carefully manages offset flow and topline thickness through the set. Longer irons feature added confidence at address with design elements that promote higher launch and greater forgiveness, while the scoring irons transition into a more compact look that preserves the precision and control expected from a Mizuno Pro iron. This progressive approach gives each iron a purpose-built profile, helping golfers experience the right blend of launch, forgiveness, and shot-making control from long iron to wedge.
Further enhancing playability is Mizuno’s Triple-Cut Sole. Engineered to improve turf interaction, the sole geometry allows the club to move efficiently through a variety of conditions while helping maintain speed and consistency through impact. The result is cleaner contact, improved control, and a more confident strike from different lies.
As with every iron in the Signature Series, the S-4 is built around Mizuno’s renowned forging expertise. Forged from premium 1025E Pure Select Mild Carbon Steel, the S-4 delivers the unmistakably soft feel that has defined Mizuno irons for generations. A copper underlay further refines the impact sensation, enhancing vibration feedback for a softer, more responsive feel.
Mizuno’s Harmonic Impact Technology sound tuning further elevates the experience at impact. By carefully managing vibration and acoustics, H.I.T. helps create the solid sound and responsive feedback preferred by accomplished players. The result is a forged iron that not only performs with added forgiveness, but also delivers the precise feel and sound expected from Mizuno Pro.
Visually, the S-4 remains true to the Signature Series identity. Its clean shaping, progressive topline, flowing offset progression, and premium finish create a confidence-inspiring look at address while concealing the forgiveness, launch, and stability built into the design. It is a player’s cavity back made to look precise, feel pure, and perform with added help where golfers need it most.
With the addition of the Mizuno Pro S-4, the Signature Series now offers its broadest performance range yet. From the shot-making purity of the S-1 to the tour-proven versatility of the S-3 and the elevated forgiveness of the S-4, the series continues to reflect Mizuno’s commitment to building irons for the diverse demands of elite players.
The Mizuno Pro S-4 represents the continuing evolution of Mizuno’s tour-driven design philosophy, bringing higher launch, greater stability, enhanced forgiveness, and exceptional forged feel together in the most forgiving Signature Series iron ever created.
Available at Mizuno Golf retailers and online at MizunoGolf.com September 17th, 2026.
MSRP: $215 USD /Club
About Mizuno Golf: Mizuno Golf is dedicated to crafting the highest quality golf equipment, combining cutting-edge technology with traditional craftsmanship. Its relentless pursuit of perfection ensures every Mizuno product meets the highest standards of performance and excellence.