In for review this week I am lucky to have the brand new Svoemesto Kayfun X RTA.

As many of your will know I’m a big mouth to lung fan, and in fact the Kayfun Lite [plus] is my go-to tank.

Svoemesto introduced the first Kayfun back in 2012, since then they have been known for (primarily) mouth to lung rebuildables.

We tell you what the term Mouth To Lung (MTL) means in our Guide To Vape Styles.

What Can We Expect From The Svoemesto Kayfun X RTA?

Svoëmesto poses this question on their website for the Kayfun X…

What makes a really good rebuildable atomizer? This is exactly the question we have
spent the last 10 years crafting answers that have proven themselves in the real world.

The Kayfun X RTA is therefore the culmination of 10 years of work and refinement. Some of their “recent” releases have included the Kayfun Prime, Kayfun 5, Kayfun Lite 2019, Kayfun 5 Squared and Kayfun Lite [plus].

Full disclosure, I own all of the above!

In fact, the Kayfun Lite (2019) was my first exposure to “high end” atomisers. Since falling in love with it I ended up getting a couple more. Now I’ve had some mixed success with high end since then, but Svoëmesto have always delivered.

Having said that they have definitely gone their own way! The Kayfun Lite was notable for including no external airflow control. It was instead controlled via a Teflon screw in the 510 assembly. The Kayfun X similarly has no external airflow control, but more about that later!

One thing that the Kayfun Lites (both variations) were missing though was top fill. It might seem crazy to people to have an atomiser launched in 2019, and refreshed in 2021 that is missing top fill. But having used these extensively for the last few years, it was a minor quibble.

With the Kayfun X they have brought in top fill. And in a very interesting and clever way…

The product in this review was purchased by myself for my own use. But since it’s such an interesting one, I thought I’d write a review on it as well!

As I’ve said before, this risks more bias than a normal review as I’ve spent my own money on this. However I will do my best to be objective, and to report back accurately on what I find, good and bad!

In The Box

  • Kayfun X Atomiser
  • Manual
  • Spares bag including o-rings and deck screws
  • QR Code Sheet

Important Note: The deck screws are not pre-installed. Instead they are sitting lose inside the atomiser, so if you tip it upside down when you first open it the screws will drop out the drip tip.


  • Dimensions – 24mm x 42.5mm (not including 510 or drip tip)
  • Capacity – 4ml
  • Airflow – 0-1.8mm continuous adjustment (requires removing from the mod + screwdriver)
  • Materials – Stainless Steel and PSU

Design and Build Quality

Anyone that has owned a Svoëmesto before will be familiar with their packaging. There’s a thin card outer box, and a stiff black cardboard box with the atomiser nestled in a foam cut out underneath the envelope containing the manual and the spares.

The general build quality is, in a word, flawless. Svoëmesto haven’t built a company that produces high end atomisers by just letting anything go out the door.

Amusingly the one thing that is missing is the ubiquitous QA Certificate you get in almost any Chinese tank. The simple fact is, they don’t need one. The name speaks for itself.

All threads are smooth, and the finish is exceptional.

The window for checking your liquid level is mad of PSU (polysulfone), so won’t shatter if you knock over your tank, and also is going to be highly resistant to “tank cracker” liquids that can react with polycarbonate.

Drip Tip

Included with the Kayfun X is a newly designed metal drip tip. This is double o-ringed and the base of it is convex to perfectly fit into the Kayfun X.

Now I’m not normally a fan of metal drip tips… and I’m sorry to say that this one doesn’t endear them to me any further. Sure it’s the best metal drip tip I’ve used, I just don’t like them very much.

Your mileage may vary. However if you want to swap to another a drip tip it’s a standard 510 connection. So I’ve often been using Svoëmesto’s “Figura” range of drip tips, which I find the most comfortable of any I’ve tested.

The Top Fill

The top fill on this directly relates to the liquid control system built into the tank. So I’ll speak about the top fill first, and then explain how it connects.

To use the top fill you lift up the top section of the tank (there are two clicks, more about the second one when we speak about the liquid control!)

Then push it back where the stylised X logo is (reminds me a little of the X-Factor logo!)

This uncovers a small kidney shaped fill hole with an o-ring surrounding it

It’s definitely easier to refill this with smaller nosed e-liquid bottles, as it is possible to get an air lock here if you’re not careful. I’ve found that 60ml Chubby Gorilla bottles are too wide to put the tip inside the fill hole, you have you to hold it carefully right against the lip when you fill.

The other thing I noticed was that as it’s hard to see your liquid level, as the top of the tank is metal and the fill hole is so small, it’s very easy to accidentally overfill and have liquid run across the top plate.

Once you’ve filled up, just reverse the process and you’re good to go.

Liquid Control

The liquid control works in tandem with the top fill. When you lift up the top section there are actually two positions. The first just raises the top fill cap as above and the base stays still.

Whereas the second lifts the whole of the tank up from the base.

It is possible to close off the liquid flow by raising the whole tank without lifting the top cap at all, you just need to hold around the body of the tank when you lift, rather than just the top cap.

Another nice touch with this design, is when you close the liquid control, you can spin the tank around so that it’s orientated how you want. If will fit down using the cog shaped base plate. Using it on a side by side and you can’t push the top back to refill? Just spin it round a little.

Airflow Control

The airflow is controlled by the “Aerokon” airflow system that Svoëmesto first developed for the Kayfun Lite [plus]. Gone is the Teflon screw from the original Kayfun Lite that just altered the amount of air coming in to the tank. Instead it uses a metal screw that screws up and down inside the 510 assembly, with the tip of it poking up to the airflow on the deck.

By raising or lowering this screw you can precisely adjust how much air is able to hit your coil from fully open (the diameter of the airflow hole is 1.8mm) to totally closed.

You obviously have to remove the tank from your mod, and then use a small flat-head screwdriver to adjust the Aerokon screw. Obviously this isn’t going to suit people that like to change their airflow on the go, instead it’s far more suited to someone who finds the airflow they like, and sticks with it.

On the base you have the Svoëmesto Logo, the name of the tank as well as your regulator marks and serial number.

The air enters the tank from the 6 equally spaced holes around the lower body, it is then directed up and to the deck, being constrained by how much your Aerokon screw is raised.

The Kayfun Lite and [plus], only had one airflow inlet, so by expanding that to 6 spaced around the tank, it stops the occasional problem of covering your airflow with a finger when you go to vape.


Anyone that has ever seen a Kayfun deck will be immediately at home here. They haven’t changed much, and why mess with something that works so well?

In the central airflow hole you can see the tip of the Aerokon screw poking through to control the amount of air.

It’s a two post deck with walls around it for the wicks to drop into. At the base of these two wick capture cups are paired liquid feed holes.

Looking inside the top section of the tank you can see the liquid ports from the top section to the base. You can also tell there’s a very small chamber that should help with flavour.

How To Build the Svoemesto Kayfun X RTA

I’m not going to run through a full build tutorial on this one, partly because it’s a pretty easy build.

However I will make a couple of notes.

When you place your coil you’ve got two options for leg placement. The standard way is to put your legs so that they go inside the post walls and get trapped by the screw coming down. If for whatever reason your coil is just a bit too long to manage this, it is possible to have your legs outside the post walls, and wrap them around the screw the other way.

My build in this example is my standard Vandy Vape Superfine SS Fused Clapton, with an inner diameter of 2.5 and 5 wraps, it comes out to about 0.5Ω.

When it comes to wicking the coil, I’d recommend drawing an imaginary line straight up from the main thread on the base and cutting it there.

For a 2.5mm coil, if you’ve got enough wick that it just barely squeezes through the coil, you’re going to want to thin the wicks out. You can afford to pull out quite a lot, then just trim them back when you’re done.

Finally for popping the wicks in the capture cups, the best way to do this is to fold them in so that the ends of the wick will be resting against the liquid ports. There’s various ways to do this, but I found the easiest way is to place your thumb against the outside of the deck, and use a pair of tweezers to gently pull it up so that you can drop the ends straight down.

How Does the Svoëmesto Kayfun X RTA Perform?

So the million dollar question, is have Svoëmesto done enough to justify the ten years of work that has led up to this tank?

I’ve been using it as my main vape for about a month now (I ordered mine on launch day) and it has paired beautifully with the Aspire Mixx which I’ve been using with the optional 21700 battery adapter.

Airflow and Cloud Production

Firstly cloud production is never going to be its strong suit. This is a purely mouth to lung tank. In terms of the airflow though, it is very smooth and due to the clever airflow control it can go from totally closed off, to a relatively loose mouth to lung vape in a continuous adjustment.

Even fully open though, you’re not going to be managing a direct lung inhale, as its 1.8mm at the widest. So this ranges from 0-4 on our 1-10 scale of tightness. Where 1 is like trying to suck a Golf ball through a hosepipe, and 10 is fully open with no restriction.

Not being able to accidentally place your finger over a single airflow hole is definitely a nice change from the previous Kayfun Lites.


I had high expectations coming into testing this. Flavour from the Kayfun Lite’s that I own is probably the best of any rebuildable I’ve tested.

Using my standard Berry Ice from SVC Labs 50/50 VG/PG I was getting great accurate flavour reproduction. I found that the metal drip tip muted the flavour a little bit, but switching to a plastic drip tip meant it was easily on par with the Kayfun Lite it shares so much of its DNA with.

As normal for mouth to lung, my Berry Ice is a 50/50 VG/PG ratio. I much prefer 50/50 for vaping mouth to lung, but there’s no reason that 70/30 wouldn’t work.

Any other notes?

One thing I always noticed with the first Kayfun Lite was that liquid managed to seep down by the Teflon screw in the 510 connector. I even noticed this happening (although less so) with the Aerokon screw when I upgraded to the Kayfun Lite [plus].

Although I can’t see that much has changed, I haven’t noticed any liquid collecting at the 510 connector. So definitely an improvement here.

Similarly there’s been no leaking that I’ve been able to spot at all. The system that closes off the liquid control seems to help massively when refilling.

The only time I’ve noticed liquid going where it’s not supposed to, is when I’ve accidentally overfilled and liquid has pooled on the top cap. When you close it again, it squeezes the liquid out so you might get a couple of drips appearing where the top cap meets the main body of the tank.


  • Great flavour
  • Top fill! (I know, it’s funny to see that as a feature)
  • Beautifully made


  • Very small fill hole
  • Only comes with a metal drip tip
  • Can’t adjust airflow on the fly (subjective)

Svoemesto Kayfun X RTA – Final Review Verdict

So does the Kayfun X do enough to become by go-to mouth to lung tank?

In a word, yes. Flavour is as good as my previous favourite tank the Kayfun Lite. Airflow is super smooth and infinitely adjustable. Build quality is flawless.

Is it going to be for everyone though? Probably not. Without even considering the price (you got get at least 4 “decent” mouth to lung rebuildables for what it costs) there’s a few quirks. Firstly there’s the fact that you cannot adjust your airflow on the go. I’ve put this down as a subjective con, as for me it genuinely doesn’t bother me in the slightest. But if you like to adjust your airflow when you’re out and about, it’s probably not going to be for you.

Similarly the small fill port is going to cause irritation for some people, especially if you like to use things like a 60ml chubby gorilla bottle. I’ve often ended up overfilling a little and that ends up squeezing some liquid out from under the top cap. If you take it slowly, and ideally are filling from a needle nosed bottle, it’s quite useable though.

But it’s a very forgiving tank for building. Some of the other so called “high-end” tanks I’ve tried are very particular about what types of builds and wicking work. The Kayfun X is much more accommodating and it’s hard to get a build that doesn’t work in there.

As always I’ll be curious to see what Svoëmesto do next, if they follow a similar trajectory that they have done with their other tanks, I fully expect to see some new finishes for the Kayfun X in a year or so. So I wouldn’t be at all surprised to see a beautiful black DLC version in the future! If they paired it with a second drip tip for those that don’t get on with metal tips, it’ll be pretty much perfect.

Let us know if you own this tank and what you think of it in the comments below!

Will Jameson - Ecigclick Vape Reviewer
Will Jameson

I started my vaping journey in 2017 with a little AIO kit. I’d made several attempts to give up smoking over the years, and I finally nailed it with vaping. I knew right away that I wanted to learn as much about all these devices as possible, and I quickly got into rebuildables and replaceable battery mods. I’ve always enjoyed kit and technology, so I’ve built up quite a collection of different tanks and mods. I love knowing how things work and what to do to get the best out of them, so sharing that knowledge and helping more people quit smoking is something I’m passionate about.

Build Quality
Ease of Use/Build
Replace if Lost or Damaged?
I started my vaping journey in 2017 with a little AIO kit. I’d made several attempts to give up smoking over the years, and I finally nailed it with vaping. I knew right away that I wanted to learn as much about all these devices as possible, and I quickly got into rebuildables and replaceable battery mods. I’ve always enjoyed kit and technology, so I’ve built up quite a collection of different tanks and mods. I love knowing how things work and what to do to get the best out of them, so sharing that knowledge and helping more people quit smoking is something I’m passionate about.
svoemesto-kayfun-x-rta-reviewFor me the Kayfun X is a nearly perfect Mouth to Lung rebuildable. It's not going to be for everyone, and it has a couple of quirks, the most notable being that it's fill port is a little on the small side. In all other respects though, it's a cracking little tank. Well made, phenomenal flavour, and easy to get on with.


  1. Is it possible Kayfun X 24mm put into Aspire Mixx with 18650 mode? I don’t want to make scratch on them. I hope you have the picture.


Please enter your comment!
Please enter your name here