Since 2019 and the launch of the ST190 series, Mizuno has quickly changed the perception around its metal woods. With the new ST-X and ST-Z drivers, along with the new ST-Z fairway woods for 2021, it is once again proving Mizuno isn’t just an iron company anymore.

The ST-X and ST-Z drivers represent the next evolution for Mizuno and are a culmination of a focused team effort to prove that, when side by side with the industry leaders, Mizuno drivers can both compete and win the battle of ball speed, spin, and dispersion.

• More photos and discussion in the forums. 

A global effort to produce better (The “how’d we get here?”)

As a global brand, Mizuno used to have a small issue with market segmentation when it came to its club releases, meaning that depending on where you were in the world, there were different metal wood sub-brands to cater to various consumers.

This worked OK for the individual markets, but overall, it wasn’t working worldwide for one simple reason—more designs meant Mizuno engineers had to stretch their biggest resource, time, thinner. It also didn’t create a lot of continuity in the products, which from a consumer-level, always made it feel like Mizuno’s approach was just “let’s give this a try!”, and it really wasn’t working.

This brings us to the “New Mizuno.” Since the original ST190 series was released in 2019 (don’t forget development started long before the release date), Mizuno has had a fully dedicated team in place working on metal wood development and technology. This has allowed engineers to work tirelessly on creating drivers that win on both a technology front as well and where it matters most: in fittings and on the course where golfers care about performance.

• More photos and discussion in the forums. 

The technology inside the 2021 Mizuno ST-Z and ST-X drivers

• SAT2041 beta-titanium faces: This titanium material is not new to the world of aerospace engineering, but as golf clubs are concerned, it had mostly been found previously in high-end JDM (Japanese domestic Market) drivers because of cost but was first used last year in the ST200 series drivers. SAT2041 has higher strength and rebound properties allowing Mizuno engineers to improve the multi-thickness areas behind the face for higher ball speed, and save mass to reposition around the head.

• New CorTech face design: Now, speaking to the faces, thanks in part to the material and Mizuno engineers’ ability to tweak and adjust based on continuous R&D, the faces of the ST-Z and ST-X drivers have been made thinner in certain areas to further optimize CT and COR, which contributes to more consistent ball speeds and additional discretionary mass.

• Using discretionary mass differently: A few grams here or there mean a lot in the golf club design world, especially when it comes to drivers. Mizuno shaved mass around the head to boost MOI in both of the new drivers and create performance separation in how they will work best for the intended players. Both of the new drivers have a carbon crown and also feature carbon panels around the sole skirt to help precisely locate the center of gravity.

Meet the 2021 Mizuno drivers

Mizuno ST-Z driver

The ST-Z replaces the ST200 and has been designed to offer the highest MOI possible without sacrificing lower spin—this driver is all about stability. Mass saved around the head, thanks to the carbon panels, along with the better-optimized face has allowed the designers to position the CG as close as possible to the neutral axis, to raise MOI, and create a neutrally biased driver. 

• More photos and discussion in the forums. 

Compared to the ST-X, the Z is longer heel to toe and slightly shallower to once again use any and all available options to maximize performance and playability.

Mizuno ST-X driver

Although the new STX driver shares a similar name to the previous ST200X designed to be an exclusively lighter weight draw-biased driver, the new STx is for any golfer seeking slightly more spin compared to the STz and also greater workability, thanks to a center of gravity positioned slightly more forward and closer to the shaft.

From the bottom, the easy way to separate the ST-X from the Z is the reduced amount of carbon on the sole and slightly more heel-biased back weight to aid the engineers in repositioning the CG.

The ST-X’s slightly deeper face and shorter heel-to-toe length help to make the driver ever so slightly more draw-biased than the ST-Z but also happens to make the driver more workable.

For those still in need of a premium lightweight option, the new ST-X has the ability to be built to a lighter and longer spec similar to the ST200X thanks to the adjustable weight in the sole, which goes from a stock 11-gram weight to just four grams when built to J-Spec. This brings the head weight to 194 grams vs. 201 grams in the standard ST-X configuration and 204 in the ST-Z. When matched with the M-Fusion shaft, you get a driver that competes against any other in the ultra-lightweight category.

• More photos and discussion in the forums. 

2021 Mizuno STX and STZ drivers prices, specs, and availability

The ST-X and ST-Z stock shaft options are directly driven from popular profiles on tour and feature a familiar story of high, mid, and low launch. The drivers will also carry a fourth shaft option, which is a carryover from the previous ST200X.

High Launch – Project X Riptide CB 50g and 60g

Mid Launch – Fujikura MotoreX F3 60g

Low Launch – ProjectX HZRDUS RDX Smoke Black 60g

High Launch and ultra-lightweight – M-Fusion

Mizuno will also continue to offer upcharge shafts options including:

• Tensei CK Pro Orange and White 60 and 70g
• Fujikura Ventus Blue and Black 60 and 70g
• Graphite Design Tour AD Di6 & 7 along with XC6 & 7

STX and STZ drivers will be priced at – $399.99

The Mizuno STX and Z driver’s pre-sale starts today January 25th, with products on retail shelves starting February 18.

Mizuno ST-Z fairway woods

Technology and design

• 3rd gen MAS1C high strength steel face: Last year, with the ST200, Mizuno completely overhauled the internal structure of its fairway woods, and the ST-Z is the next evolution. Similar to the driver, engineers have improved the CorTech multi-thickness pads behind the hitting area to raise ball speeds while also improving sound and feel

• Carbon crown: When it works, it works, and the carbon steel crown of the ST-Z fairway woods reduces mass from higher in the head and gives the engineers the ability to better position it to deliver the performance variables they are searching for.

• New shaping: After all the material and sciencey stuff were figured out, the last part of the new fairway woods to consider was the shape. It seems simple, but the shape not only has a huge impact on the club’s physical performance, but it plays a major factor in how golfers perceive it in the address position. The leading edge and the hosel transition have been adjusted to appeal to the target players and make it more efficient from the turf, which is where most players will use their fairway woods the most.

Specs, prices, and availability

The ST-Z fairway woods will be available in the lofts of 15 and 18 degrees, and with Mizuno’s Quick Switch adjustability, the fairway woods can go up and down two additional degrees.

The stock shaft configurations for the ST-Z will be the Fujikura MotoreX 7 in stiff flex and the ProjectX RipTide CB in regular.

The ST-Z fairway woods are priced at $299.99 with pre-sale and fitting tools available starting today January 25th with the product on retail shelves on February 18.

• More photos and discussion in the forums.