Mizuno JPX921 Irons Revealed

All the details on the four new irons in the new JPX921 range from Mizuno

Mizuno JPX921 Irons Review

Mizuno has launched its new JPX921 iron range comprising four models offering different looks and performance to appeal to a range of handicaps

Mizuno JPX921 Irons Revealed

Mizuno has replaced its popular JPX919 range with a quartet of JPX921 models promising across-the-board improvements.


The biggest change can be found on the JPX921 Forged, which integrates the Chromoly 4120 we saw on the previous Hot Metal model into a full body forged iron for the very first time. This allows for a clubface up to 0.5mm thinner, which along with stronger lofts in the 4-8-iron delivers the fastest ball speeds Mizuno has ever produced from a full body forged iron.

RELATED: Mizuno JPX921 Irons Review

Additional perimeter weighting with toe bias creates a Stability Frame to maximise results from off-centre strikes, while a 6.4 per cent wider CNC back milled slot further increases stability.

Despite this, the JPX921 Forged iron offers a sleeker, more compact profile with a shorter blade length throughout than the previous version, a beveled edge and reduced offset.


Mizuno JPX921 Tour

The JPX921 Tour maintains its predecessor's fusion of precision with stability from off-centre strikes. A thicker cavity pad provides a softer feel while the short irons boast narrower soles for smoother turf interaction.

Mizuno’s Stability Frame with toe bias weighting promotes a longer, straighter and more consistent ball flight while the pearl brush finish reduces glare.


Mizuno JPX921 Hot Metal

The JPX921 Hot Metal is the longest iron in the range, thanks to the use of Chromoly 4140M and a re-engineered Cortech face, now 0.2mm thinner across the centre point, creating faster ball speeds. These are assisted by a Seamless Cup Face featuring a variable thickness sole design that allows the leading edge to act as a hinge, generating more face flex.

IRONS TEST: Mizuno JPX919 Hot Metal v Hot Metal Pro


Golfers also have the option of the JPX921 Hot Metal Pro, which features the same technologies in a more compact package with less offset, while left-handers can be fitted into the Special Edition Leftie (SEL) set. It combines JPX921 Forged long irons (3 and 4-iron) and JPX921 Tour mid and short irons (6-GW) with pre-adjusted lofts for perfect distance gapping between the models.

The JPX921 irons go on sale September 17th with the following RRPs: JPX921 Forged £150 per iron, Tour £150 per iron, Hot Metal Pro £135 per iron, Hot Metal £120 per iron.

Mizuno JPX Fli-Hi

To replace the long and mid irons, Mizuno will also offer the option of the JPX Fl-Hi.

Mizuno JPX Fli-Hi Hybrid Launched

They use an adapted flow of loft and shaft length in combination with an updated construction to hit more precise, consistent gaps from 4-7-iron.

The new Fli-Hi’s wider footprint and material construction deliver an even more playable, high flying alternative to their predecessors. A 17-4 stainless steel face and 431 body deliver an upgrade in ball speed, while the bendable hosel allows for adjustments in lie angle.


A graduating profile from fairway wood type to hybrid type is a subtle adaptation on previous models. The 20 degree (#4) has a wider fairway type profile, moving towards a tighter hybrid type shaped 29 degree (#7) with a deeper face.

The new Fli-Hi #7 is built to the exact loft and length spec as the JPX921 Hot Metal 7-iron. At the longer end, the Fli-Hi #4 uses a little more loft and a slightly longer shaft than the JPX921 Hot Metal 4-iron. Testing showed this set-up proved easier to hit the right distance consistently.

The Mizuno JPX Fli-Hi is available as a 4-7 -iron replacement in RH only with an RRP of £135.

Joel Tadman
Technical Editor

Joel has worked in the golf industry for over 12 years covering both instruction and more recently equipment. He now oversees all product content here at Golf Monthly, managing a team of talented and passionate writers and presenters in delivering the most thorough and accurate reviews, buying advice, comparisons and deals to help the reader find exactly what they are looking for. So whether it's the latest driver, irons, putter or laser rangefinder, Joel has his finger on the pulse keeping up to date with the latest releases in golf. He is also responsible for all content on irons and golf tech, including distance measuring devices and launch monitors.

One of his career highlights came when covering the 2012 Masters he got to play the sacred Augusta National course on the Monday after the tournament concluded, shooting a respectable 86 with just one par and four birdies. To date, his best ever round of golf is a 5-under 67 back in 2011. He currently plays his golf at Burghley Park Golf Club in Stamford, Lincs, with a handicap index of 3.2.

Joel's current What's In The Bag? 

Driver: Titleist TSR3, 9° 

Fairway wood: Titleist TSR3, 15° 

Hybrid: Titleist TSi2, 18° 

Irons: Ping i230 4-UW

Wedges: Titleist Vokey SM8, 54°. Titleist Vokey SM9 60° lob wedge, K Grind

Putter: Evnroll ER2V 

Ball: 2023 Titleist Pro V1x