Hands-On Review of the MB&F Horological Machine No. 9 (HM9) "Flow"

As a fan of the Swiss independent watchmaking scene, I am always excited when I get to try out a new and incredibly unique timepiece. This was exactly the opportunity I was given when the great folks at MB&F let me borrow an MB&F Horological Machine No. 9 “Flow” recently.

MB&F is certainly known for their daring designs, limited production runs, and intricate complications. The HM9 “Flow” hits all these points. One might consider the Horological Machine line more avant-garde than MB&F’s sister line, the Legacy Machine (or LM). With the Legacy Machines, MB&F has opted for a more traditional circular case and dial design (with tons of unique aspects for sure). However, with the Horological Machines, MB&F has been very willing to experiment with all types of design aesthetics rarely seen in modern watchmaking.

It was this boldness that drew me to the HM9. This watch is surely not understated. The HM9 has unique lines and curves and multiple windows into the in-house manual wind movement. Upon wearing it out for the first time with friends, I got numerous comments that I had a spaceship, airplane, or car on my wrist. The dual barrel-esque case was clearly meant to evoke thoughts of classic cars and planes (think the 1930s-50s). Because of this dual inspiration, MB&F created two versions of the HM9 “Flow", the “Air” version and the “Road” version. The vertical dial on the Road version resembles a car speedometer while the dial on the Air version resembles a traditional Pilot’s watch dial. For my review I had the Air model in titanium.

The watch is delightfully steampunky and has unique dial shape that has two barrels or “engines” that house two fully independent balance wheels with planetary differential. It is quite the visual treat to see them operate completely independently of each other in the watch’s viewing windows. MB&F does a good job creating windows in their watches that showcase their beautiful movements without it seeming out of place or “too much.” Indeed, MB&F recently created a variation of the HM9 with a sapphire case where the entire movement of the watch is visible. I would love to get my hands on one of these pieces for a follow-up review.

While the watch is large at 57mm × 47mm × 23mm, it wears smaller and almost wraps around your wrist. I didn’t feel awkward wearing the piece on my 6.75 inch wrist. I mean, it is a big watch that is going to attract attention, regardless of your wrist size. However, due to it’s design, the watch still looks good on even modest size wrists. I generally don’t spend a lot of time on straps, but the calf-skin strap was uniquely designed for the watch, and fits it well. I’m not sure how you would define the strap, but it’s comfortable, unique (like the watch) and fits in the overall retro-vintage look that MB&F is striving for with the watch.

MB&F also pays attention to the details in their watches. As noted earlier, the HM09 “Flow” Air has a traditional pilot’s dial. I was delighted to find the small dial had lume on the hands and all the indices. A nice touch that you might not expect from such an avant-garde piece. Beyond that, the watch is water resistant to 3ATM or 30 meters (but really, who is taking this watch for a swim?) and the 301 component and 51 jewel manual-wind movement has a 45 hour power reserve.

One of the great things about MB&F is that when you buy one of their pieces, you will most likely be the only person you know with that piece. That is because all of their pieces (even if they are not actually a limited edition) are created in very limited quantities. The HM9 “Flow” Air in titanium is limited, though, and to just 33 pieces. When you are spending the kind of money on a watch like a Horological Machine, you want it to be limited.

Ultimately, the HM9 like most of the Horological Machines, are divisive timepieces. Nobody will question the research, attention to detail, and craftsmanship that goes into each piece, but the designs are not for everybody. I would say MB&F’s Horological Machine line offers pieces that are even more avante-garde and unique that Richard Mille watches. I fall into the camp that really likes most of their offerings. I appreciate that a watch brand is willing to take some very wild chances with their watches and believe MB&F succeeds pretty much any time they release something “different.” At the end of the day, MB&F doesn’t need to appeal to everyone. They just need a few devout watch collectors to “get it.” And if you want something more traditional, MB&F still has their Legacy Machine line. You can check out our review of the MB&F Legacy Machine LM Perpetual EVO Titanium here.

How much is the MB&F HM9 “Flow” Air?

The MB&F Horological Machine 9 “Flow” Air is limited to just 33 pieces and retails for $193,000 USD. You can pick find out more about the piece at MB&F’s website.