Mizuno’s new ST-X and ST-Z drivers are the culmination of the Japanese company’s three-year, rapid-fire development project.
The follow-up to the ST190 and ST200, Mizuno’s first drivers widely played on tour, the ST-Z and ST-X use Mizuno’s second-generation SAT2041 Beta Ti face and complex carbon construction, designed to to deliver fast ball speeds and a dense, satisfying sensation at impact.
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“Most of our ST200 tour feedback was on the sensory side, a desire for a sound our players generally described as solid or dense,” said Chris Voshall from Mizuno.
“We spent the next year working on improving feedback, hand in hand with releasing the additional ball speed we knew was left in our SAT2041 Beta Ti face.”
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SAT2041 stands for Super / Alloy / Titanium / 20% Vanadium / 4% Aluminium / 1% tin and it offers 17% more tensile strength and 8% more flexibility than traditional 6-4Ti.
A Nippon steel product that was developed over five years as a lightweight, high strength material for the automotive industry and used for complex cycle parts requiring intricate design and an ability to withstand strong forces, SAT2041 has a fine grain structure inherently resistant to fatigue.
As a high strength Beta Ti, SAT2041 maintains its characteristics and resists micro fractures for longer than the commonly used 6-4, Alpha Beta Ti.
The ST offers a choice of two different head designs in the driver, with characteristics to suit different playing requirements and deliver different ball flights, and a stable, low-spinning fairway wood option.
Mizuno ST-Z Driver
The ST-Z driver has been designed to be ultra-stable and to offer low-spin efficiency.
Featuring the 2nd generation of Mizuno’s Forged SAT2041 Beta Ti face, it has a balanced toe/heel carbon composite construction with deep central back weight for a straight ball flight.
“The ST-Z’s predecessor the ST200 had a reputation for being a straight-line bomber favoured by our longer hitting tour players, and the ST-Z profile is no different,” said Chris Voshall.
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“But with a year’s extra experience of engineering Forged Beta SAT2041 Ti. we were able to release a little extra ball speed and a much more satisfying experience off the clubface.”
A balanced use of carbon composite on the sole and a deep central sole weight are biased towards a straight-line flight and low spin efficiency.
The ST-Z driver has a wide, low footprint, with a neutral visual lie angle and comes with four degrees of quick switch adjustability to fine-tune look and trajectory.
Available in 9.5° and 10.5°, Mizuno offer Project X HZRDUS Smoke Black, Fujikura Motore XF3 and Project X Riptide CB shafts as standard, with the driver’s RRP at £399.
REVIEWED AND TESTED: Mizuno ST-Z driver
Mizuno ST-X Driver
The ST-X driver features a draw-biased carbon composite construction aided by a heel side sole weight. Like the ST-Z, it’s built upon the second generation of Mizuno’s Forged SAT2041 Beta Ti face.
“In testing, a lot of our tour players preferred the ST-X over the ST-Z for its deeper shape and slightly smaller profile,” said Chris Voshall.
“I’d recommend starting with an open mind and dropping the ST-X alongside the ST-Z in the address position. For a draw bias driver, it’s not going to be what most players expect.”
An expanded toe located carbon composite window, with a heel located sole weight combine to produce a reliable draw bias. The ST-X driver offers a more compact profile, a slightly deeper back portion and more upright visual lie angle and also comes with four degrees of quick switch adjustability.
As with the ST-Z, the ST-X offers more dense feedback through impact and a more muted, powerful tone.
Available in 9.5° and 10.5°, Mizuno offer Project X HZRDUS Smoke Black, Fujikura Motore XF3 and Project X Riptide CB shafts as standard, while those with mid-lower swing speeds will benefit from the J-Spec, Japan Specification, incorporating an incredibly lightweight 39g MFUSION graphite shaft.
The driver has an RRP of £399.
REVIEWED AND TESTED: Mizuno ST-X driver
Mizuno ST-Z Fairway Wood
Offering high levels of stability and low spin efficiency, the ST-Z fairway woods offer a throwback profile, with curves for the purist and performance for the pragmatist.
Mizuno’s third generation MAS1C face is Mizuno’s most powerful to date. The ST-Z fairway woods provide a balanced package of low spin performance and stability, not common in most fairway woods.
Both 3-wood and 5-wood have an adjustable, quick switch, hosel offering four degrees of loft and face angle adjustability.
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The ultra-lightweight carbon crown lowers the COG for better spin vs MOI performance, while re-engineered WAVE Technology, delivers a compact wave design that lowers the mass.
“The fairway wood might be the least regularly changed club in any bag so we spent a lot of time looking at older models that our tour players had hung onto over the years,” said Chris Voshall.
“It ended with a lot of really subtle touches on the ST-Z, like leading edge and transition into the hosel. There’s a lot to like at address.”
The ST-Z fairway wood is available in 15º and 18º with an RRP of £279.
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