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CFX keycap

CFX is a new low-pro keycap profile: 16.5x16.5mm square caps available at Chosfox in different colors.
Published July 22, 2022
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CFX (or Chocfox), this new low-pro keycap profile, is offered by Chosfox in different colors and materials.

At the time of writing this, the black and white PBT, and the frosted transparent white PC caps are available. They started shipping today btw.

Transparent black is no longer available and the transparent pink is a sample to demonstrate that we can produce custom colors – Chosfox.

The 16.5x16.5mm size makes it possible to use them on narrower-pitch keyboards.

There is only this 1u spherical keycap on offer at the moment. The second batch will hopefully add a homing key, other sizes, and caps with legends, as well as more color options are planned too.


If you witnessed the unfortunate and quickly removed first announcement on Reddit (Jun 30), you know why I was cautious about this cap. So I asked for some samples to get a first-hand experience on them before posting anything.

In addition, I reached out to MBK-designer @mburger and original manufacturer FKcaps (among others), and I got the green light from them too.

So without fueling the drama, let's focus on the CFX caps with a very quick first impression post and some close-ups. A more in-depth comparison will follow later, involving other low-pro profiles.


Surprisingly, the CFX profile wasn't inspired by MBK in the first place but by square Apple caps, DSA and SA.

The square footprint cames from Apple, the spherical dish from DSA, and the curved walls from SA.

Nevertheless, there's no way to talk about CFX without comparing it to MBK.

First impressions

Very similar to MBK on the first look, but on closer inspection, it differs in almost every aspect.

Take a look at the regular square shape of the top surface, its rounded corners, etc. Using CFX keycaps, especially on ortholinear boards, may result in very clean looking builds.

Obviously, the width is different (17.5 vs 16.5mm) which affects the weight as well: the CFX is about 2g lighter compared to MBK.

Pic: MBK (left) vs CFX (right)

MBK (left) vs CFX (right)

Surface/touch: the CFX is slightly but palpably smoother. I'm not sure if this photo can reflect the difference in the graininess of the top surface:

Pic: MBK (left) vs CFX (right)

MBK (left) vs CFX (right)

When mounted, the two profiles are basically the same height. If the CFX looks higher in the photo above that's because its stems are longer. Other than that, they are also more chamfered.

Pic: MBK (left) vs CFX (right)

MBK (left) vs CFX (right)

The back of the CFX is very basic compared to the much more fancy MBK.

Samples vs final product

However, the design of the CFX has been evolved since these samples were sent out (July 4) and I was informed that the bulk product offered these days is slightly different.

The longer, almost pointy stems were changed to the more classic stem shape "to increase stability", just like on the original Kailh Choc caps. (However, I liked the pointy stems a lot and didn't have any problem with them.)

Pic: Pointy, chamfered stem. Discontinued?

Pointy, chamfered stem. Discontinued?

And the tail at the corner caused by the injection hole has been fixed for bulk orders. There is still a visible part, but they don't stick out anymore. (Btw, it wasn't particularly annoying or any worse than by other profiles.)

Pic: Fixed injection issue

Fixed injection issue

Mounted on some plates

Sorry, I had only MX-spaced plates at hand.

But I put up a gallery on imgur anyway:


While obviously not a revolutionary new design, CFX is definitely not a clone either. It's a new keycap profile but with only tiny differences compared to existing keycaps. People probably won't flock to Chosfox to replace their existing low-pro sets but from now on CFX will be there as an alternative.

Asking around in the industry I got the impression that some of the players – who are also actively involved in the low-pro community – see CFX as a missed opportunity, mostly because it doesn't really stand out. However, not all new products have to be a bombastic new innovation.

And all the big names I talked to told me in general that they are glad there is a new keycap profile that comes to market because it indicates growth in the segment and the community deserves to be able to pick from a wider range of options.


That said, you can vote with your money right away at:

Btw, Chosfox offered you a 5% discount (coupon code: KBDNEWS, over $49).

And stay tuned for a more in-depth comparison, involving other low-pro caps.

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Published on Fri 22nd Jul 2022. Featured in KBD #88.


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