MAS Irukandji

Manufacturer: MAS Watches | Price: £189 GBP (Kickstarter Price) $235 USD, €210 EUR approx))

The MAS Irukandji is a feature packed dive watch, aptly named after a group of highly venomous jellyfish, found on the coastline of Australia. The Irukandji has a very unique design with a huge range of premium features with a fit & finish usually found on much higher priced timepieces. The Irukandji is just like its namesake; small in size, but packing a serious wallop! Shown below are the launch colour options of the Irukandji, with the possibility of more being added.



  • Dimensions: Case – 41.8mm (39.7mm at Bezel), Thickness – 14.8mm, Lug to Lug – 45.8mm, Lug Width – 20mm
  • Movement: Seiko NH35 Automatic, 21,600vph (3Hz), Date Complication, Hackable, Self Winding, 40hr Power Reserve
  • Case Material: Brushed 316L Marine Grade Stainless Steel, Drilled Lugs
  • Weight: 87g     Extras: Watch Roll, Additional Strap
  • Straps: Matching Two-Piece Nylon with Signed Buckle and Choice of Additional Canvas or Rubber Strap
  • Crystal: Domed Sapphire, AR Coating
  • Bezel: 120 Click Unidirectional, Fully Lumed Ceramic Insert
  • Water Resistance: 20ATM / 200m / 660ft
  • Lume: Swiss Super Luminova® BGW9
  • Crown: Signed, Screw Down      Caseback: Brushed & Polished, Stamped Irukandji Logo, Screw Down
  • Warranty: 2 Years     Where to Buy: MAS Watches / Campaign currently running on Kickstarter
  • Options: Colours: Reef Blue / Deadly Black / Stinger Pink | Crown Position: 10 or 4 o’clock

MAS Irukandji 1

Matthew & Son Watches

Matthew and Son, or MAS Watches, was founded by Matthew Francis, a watch enthusiast and father, who shares his love of watches with his young son, Tate. (Hi Tate, if you’re reading thisEmoji401). Matt, having worked with some of Australia’s best known brands for many years, it was time for him to scratch that entrepreneurial itch and turn a personal obsession into a way of life. What better way to do it than with family by your side? So, with much excitement, MAS Watches was born! Motivated by a passion for both the aesthetics and engineering of all timepieces, but particularly wristwatches, Matthew and Son seek to design and produce uniquely styled, high quality timepieces with a fit and finish that appeals to other watch enthusiasts.
MAS Irukandji 2

The Case

The Irukandji measures in at 41.8mm diameter at the base of the case, tapering to 39.7mm at the bezel. The lug to lug I measured at 45.8mm and has a thickness of 14.8mm including that domed sapphire crystal. This uniquely designed watch is incredibly wearable and the finishing of the fully brushed case is absolutely fantastic. Due to the relatively short lug to lug it would fit extremely well on a variety of wrist sizes from I’d say, around 6.25″ and above.

The entire case, bezel, caseback and crown are all 316L marine grade stainless steel. The Irukandji has a water resistance rating of 200m / 660ft, thanks to the screw-down caseback & crown. Talking of the caseback & crown, they are both deeply stamped with the Irukandji / MAS logo, a very nice addition in my opinion. None of that lightly etched crap you get on some other brands that I won’t mention. Well done Matt, it’s attention to detail like this that makes a difference to us watch enthusiasts / watchaholics!
Oh yeah, before I forget, the case also features drilled lugs making it simple to swap out straps quickly. I love that feature on any watch, it makes a huge difference if you swap straps as much as I do. You’d be amazed at how much of a difference this makes to any watch. It’s similar to changing the alloy wheels on a car. It totally transforms the look & feel of it. Anyway, moving on…
MAS Irukandji 3


The Irukandji comes fitted with a colour matched two piece nylon strap (120mm, 80mm (excl buckle]) with a rather fat, chubby looking single keeper which is better in my opinion than the normal two wee skinny keepers. Inside the watch roll that comes included is an additional spare strap. At the time of ordering or at the end of the Kickstarter campaign you are given the option of picking a spare canvas or rubber strap. If the Kickstarter campaign reaches its 2nd stretch goal there will also be a stainless steel bracelet option, although I can’t really comment on the quality of the bracelet as I wasn’t sent one.
MAS Irukandji 4

The buckle of the strap that came fitted to this prototype is signed with a neatly done MAS logo however, it’s also polished which I found a bit odd seeing as the case is entirely brushed. I have spoken to Matt regarding this and he said it is something that will be looked at on the final production model. I did find it a bit weird that none of the other people that reviewed the prototype never picked up on this. Ah well, maybe my OCD does have it advantages.

MAS Irukandji 5


The movement fitted to the Irukandji is the microbrand go-to movement of choice, the super-reliable Seiko NH35. A great workhorse that is a 21,600vph, 3Hz, 24 jewel movement with self winding and of course hacking. Checking the accuracy after running the Irukandji after just a few days, mainly on my wrist and occasionally in my Barrington winder, I thought the accuracy was amazing, with it showing an average of +0.6 seconds per day. 
I have spoken to Matt regarding this and the prototype was regulated before being sent out. Matt additionally said that all Irukandji production models will be regulated in-house before being shipped out to the customer. That is astonishing and I wish more microbrands done this!
The movement has a 40 hour power reserve meaning a fully wound Irukandji will last for almost 2 days while off the wrist or not in a watch winder. There isn’t much else to say about the NH35 movement, it is what it is. Reliable, a total workhorse and inexpensive to get serviced when the need arises.

Dial & Bezel

The Irukandji has a 120 click unidirectional bezel with a fully lumed ceramic insert. It is of great quality and everything lines up perfectly even on this prototype. The bezel action is very good with no backplay.  The bezel action itself reminds me of the brilliant Traska Freediver.
The dial has very neat indices all around. The text is all very neatly printed and very legible. There is also a date complication at the 3 o’clock position. The syringe style hour and minute hands are also very much in proportion to the dial and actually suit the watch very well. The matt black on the dial is just perfect while the pink and blue versions of the Irukandji will have a sunburst effect.
The lume on this prototype is basically a test bed of what MAS are working towards for the production models. Matt has assured me that the lume has already been rectified and is ready to go for the final product and will be even stronger / longer lasting with BGW9 being used on the dial, hands and bezel.
MAS Irukandji 6


A fantastic watch that is brilliantly proportioned and would fit extremely well on a lot of different size wrists. It is very well made with a great tool-like brushed aesthetic. It’s definitely worth the early-bird price they are asking for it! It is for sure, another great diver watch that punches well above its weight. Is this another entry level automatic watch that’s better than the Seiko equivalent? Hell yes, you better believe it!
I like this watch so much that I’m now personally backing MAS Watches Kickstarter campaign. You can’t get much of a better recommendation than that! Although, if I could change anything, I’d swap the stretch goals. A stainless steel bracelet would be a much more important option to me than just another colour.
MAS Watches – Definitely a brand I’ll be watching closely as they mature over time.
[Brilliant bang for your buck! Matt, if you iron out the little prototype niggles for the production model, I’d no doubt give it a score of 9/10). (I will be getting a production model once they’re ready, so I’ll come back and edit my score if necessary).

A huge thank you to Matt & Tate from MAS Watches for sending out the Irukandji prototype so promptly, and all the way from Australia! I wish you and Tait all the very best for the future and good luck with your current Kickstarter campaign. (Not that you’ll need it). *Edit – Campaign now fully funded!*
To view the MAS website, or join their mailing list to be informed of updates and future releases, visit Matthew & Son Watches.

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