Equipment
Mizuno adds Pro S-1 irons to Signature Series lineup
Mizuno has unveiled the latest addition to its Signature Series with the release of the Mizuno Pro S-1 irons. Designed as a true muscle back set, the S-1 is aimed squarely at better players who value shot-shaping ability, refined feedback, and clean turf interaction, the company says.
Building on the popularity of the Mizuno Pro S-3 irons released earlier this year, the S-1 offers a different profile and performance characteristics suited to players with a more traditional preference in blade design.
For comparison, a Pro S-3 iron is pictured below.
Let’s dig in to some additional details.
Mizuno Pro S-1 irons: Key features
Grain Flow Forged Construction
- No surprise here. The S-1 irons are forged in Hiroshima, Japan, from a single billet of 1025E Pure Select Mild Carbon Steel. Mizuno’s forging process, used across its better-player irons, is intended to deliver consistent shaping and precise feedback.
Copper Underlay for Enhanced Feel
- Ditto. A layer of copper beneath the chrome finish helps soften vibration and improve the sensory connection at impact, which Mizuno has used in recent models and continues here.
Channel Back Design
- By carving a shallow channel into the back of the clubhead, Mizuno engineers were able to redistribute mass to improve vertical stability. The result is a more predictable launch and center of gravity placement without altering the traditional blade appearance.
Refined Sole Geometry
Compared to the Pro 241 blade, the S-1 introduces:
- Flatter camber
- Sharper leading edge
- One additional degree of bounce
These changes are intended to reduce digging and offer more forgiveness on slightly shallower strikes.
Tour-Inspired Aesthetics
- The S-1 features a compact shape with a square toe, thin topline, and straight edges. Its Soft White Satin finish is subtle and designed to reduce glare at address.
Pricing, Specs, and Availability
Pricing: $215/club
Availability: The Mizuno Pro S-1 irons will be available through authorized Mizuno fitters and retailers beginning August 2025.
Stock shaft: KBS Tour
Stock grip: Golf Pride Tour Velvet
Full specs below
| MIZUNO PRO S1 | 4 | 5 | 6 | 7 | 8 | 9 | PW |
|---|---|---|---|---|---|---|---|
| Loft | 24° | 27° | 30° | 34° | 38° | 42° | 46° |
| Lie | 60.5° | 61° | 61.5° | 62° | 62.5° | 63° | 63.5° |
| Length | 38.75″ | 38.25″ | 37.75″ | 37.25″ | 36.75″ | 36.25″ | 35.75″ |
Neal Shipley was the first to admit that he enjoyed his food while in college. But since his days at Ohio State, he’s slimmed down and earned a PGA Tour Card.
That hasn’t stopped him from having fun with his wedge stampings, though it’s led to some misunderstandings.
On the 54 (degree), we have ‘Big Fudge,'” Shipley told GolfWRX. “It was supposed to be ‘Big Fridge,’ so this happened a little while ago. ‘Big Fridge’ was a nickname between my college teammates and I, with ‘fridge’ meaning stomach, a big stomach.
“We told the Ping guys to put … ‘Big Fridge’ on it, and I think maybe some bad cell service or something, and they thought I said ‘fudge,’ so they put fudge on it.”
On Shipley’s 50-degree he also continues the food theme, this time with his go-to order at the “Golden Arches,” and his stamping “DONS 7.”
“The number 7 meal, the two cheeseburger meal, that was my McDonald’s order, back when I would have McDonald’s frequently,” Shipley shared.
At GolfWRX, we are a community of like-minded individuals who all experience and express our enjoyment of the game in many ways.
It’s that sense of community that drives day-to-day interactions in the forums on topics that range from best driver to what marker you use to mark your ball. It even allows us to share another thing we all love – buying and selling equipment.
Currently, in our GolfWRX buy/sell/trade (BST) forum, @raw10628 has a L.A.B. DF3 putter and Masters putter cover up for grabs.
From the listing: “Some great items here today, time to thin out and make room for next set of gear. All prices include shipping.
LAB DF3 Purple 33.5” 68° lie with TPT – $725. LAB Masters release DF3 cover – $150.”
To check out the full listing in our BST forum, head through the link. If you are curious about the rules to participate in the BST Forum, you can learn more here: GolfWRX BST Rules
Driver: Ping G440 LST (9 degrees)
Shaft: Accra TourZ Green 5-M4
3-wood: Ping G440 Max (15 degrees)
Shaft: Accra TourZ Green 6-M4
5-wood: Ping G440 Max (19 degrees @18)
Shaft: Accra TourZ Green 6-M4
Hybrid: Ping G440 (23 degrees)
Shaft: Oban Isawa Red Hybrid Shaft 04 Flex 70 Gms
Irons: Srixon ZXi7 (5-P)
Shafts: Aerotech SteelFiber Private Reserve i80
Wedges: Cleveland RTZ (50-MID, 54-FULL, 58-MID)
Shafts: Aerotech SteelFiber Private Reserve i105
Putter: L.A.B. Golf OZ.1i
Shaft: ACCRA Putter Shaft
Grips: Golf Pride Tour Velvet
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Benny
Jul 15, 2025 at 8:41 am
So dang pretty. Nothing better than Mizzy’s blades. It sounds like these are Mp5 replacements with the “channel back design”.
ZBubby
Jul 26, 2025 at 9:31 am
I hope the top line isn’t as fat as the MP-5’s. I have MP-4’s and couldn’t upgrade due to that chunkier flange.