WARNING: This product contains nicotine.
Nicotine is an addictive chemical.

WARNING: This product contains nicotine. Nicotine is an addictive chemical.

Eleaf iJust 21700 Kit | Review

We're gonna a need more power!

8 min read

We independently review everything we recommend. When you buy through our links, we may earn a commission. Learn more›

Aspire AVP AIO Pod

Eleaf’s iJust line has been around for as long as I can remember. Their latest offering is the iJust 21700, which (if it wasn’t evident by the name) is a 21700 version of the iJust 3 that we reviewed last year.

It also comes with the Ello Dura tank, but this time we have version two of the Eleaf Mesh coils, and a new top-fill system.

The Eleaf iJust 21700 kit is available in 5 colors: Purple, Dazzling, Silver, Red, and Black.

The Good

Solid build quality, good sub-ohm tank with decent mesh coils.

The Bad

Unfortunately not enough power for optimal coil performance.

The Bottom Line

There’s nothing inherently wrong with all the pieces of the iJust 21700 kit, in fact, they are pretty good. I think the Ello Dura tank and new M2 & N2 mesh coils are Eleaf’s best yet – Sadly, there just isn’t enough power from the direct power output 21700 to make the most of those coils.


Disclosure: This product was sent to us by Vapesourcing for the purpose of this review.

iJust 21700 Mod Specs

  • Height: 120mm
  • Diameter: 25mm
  • Made of Zinc Alloy
  • 80W Maximum
  • Direct-Output Wattage, Non-Adjustable
  • LED Battery Indicator
  • Uses one 21700/20700/18650 Battery

Ello Duro Tank Specs

      • Height: 28mm
      • Diameter: 25mm
      • Made of Stainless Steel
      • 5.5ml Max Capacity
      • Dual Bottom Airflow
      • Top-Filled
      • Multiple Coil Options

In the Box

      • Eleaf iJust 21700 mod
      • 21700 Battery (optional)
      • 18650 Battery Adaptor
      • Eleaf Ello Duro tank
      • HW-N2 0.2ohm coil
      • HW-M2 0.2ohm coil (pre-installed)
      • QC USB cable
      • Manuals
      • Spare parts
Design & Style9.5
Eleaf iJust 21700 Kit

There’s not too much to go over with the design and styling of the new Eleaf iJust 21700.

It’s very much as you’d expect an almost replica of the iJust 3, but with a removable battery.

The few differences are with the pattern engraved along the battery tube, this time it’s more subtle lines.

Then there’s the glaringly obvious difference of the shape of the extension tank for the Ello Dura. I’ll call it a bubble tank, but it’s far from a bubble. It actually bulges out more toward the bottom and reminds me of a lava lamp.

Eleaf iJust 21700 Kit

The other key difference is that the iJust 21700 has a battery cap on the bottom of the device. It has the same knurled effect on the base, which makes it easy to grip, and the threading of the battery cap is very smooth and easy to remove.

We still have a funky shaped fire button. This time instead of a hexagonal shape, it matches the same form of the new bubble tank included with the Dura tank.

The fire button is surrounded with an LED light to show battery status, and there’s a micro USB port on the back of the device for charging.

Eleaf iJust 21700 Kit

It’s quite difficult to make a device of the tube mod style, that can stand out from the crowd, as there’s not much to work with from a styling point of view.

Yet, you still glance at the iJust 21700 and know instantly it’s an Eleaf device and it’s part of the iJust range. It won’t wow you with its design, but it’s not ugly.

Eleaf iJust 21700 Kit

Build Quality

You might think there’s not much that could be wrong with the build quality of a standard style vape pen. But I’ve held plenty that felt cheap and bad quality.

Thankfully that’s not the case with the iJust 21700. Everything from the engraving on the body, to the 510 connection and the battery cap are well engineered.

The battery cap has good, smooth threading and the same can be said of the Ello Dura tank.

The fire button is clicky and responsive, but I do wish the LED lights were a little more prominent.

Eleaf iJust 21700 Kit


As you’d expect for a 21700 vape pen, it’s not the smallest device going and is undoubtedly going to be noticeable in your pocket.

The IJust 21700 device measures in at 120mm tall and 25mm in diameter, without the Ello tank on top, and another 28mm with it.

Eleaf iJust 21700 Kit

The iJust 21700 Kit is a simple to use vape pen, with relatively few features.

As you’d expect the iJust 21700 can use either 21700, or 18650 batteries (with the included sleeve). It’s also a direct output device, which means as the battery drains, the power will also deplete.

There are no adjustable power features, and it has a maximum power output of 80W.

It does come with the standard circuit protection system to prevent over-charging, over-current, and over-discharging of the battery.

The iJust 21700 also features 1amp charging and passthrough for vape while charging.

Eleaf iJust 21700 Kit


Clicking the fire button 5 times turns the device on and off, which is indicated by the flashing LED’s behind the fire button.

Then it’s just a case of hit the fire button when you want to vape – simple.

Eleaf iJust 21700 Kit

LED Indicator

There is an LED light which goes around the outside of the battery to indicate remaining battery level when you fire.

      • Green = 100-60%
      • Orange = 59-30%
      • Blue = 29-10%
      • Flashing red = below 9%

While the indication levels are clean and simple, the light itself isn’t the most visible. I would have much preferred Eleaf use larger LED, or lace the indicator elsewhere.

Eleaf iJust 21700 Kit

The Ello Dura tank comes in two variants with a 4ml capacity straight glass, and a 5.5ml capacity bubble glass, which is more like a lava lamp shape than your typical bubble glasses.

The tank has 3 large airflow holes around the base which can be easily adjusted with the knurled AFC ring, which also has a nice smooth turn to it.

Eleaf iJust 21700 Kit


Eleaf has upgraded the top fill system on the Ello Duro since we last saw it come with an iJust device.

Now there is a safety locking mechanism or child safety top cap.

You have to twist the top cap 180 degrees, before being able to use the push to slide mechanism.

It’s a far better system than before, it helps prevent any accidental opens, and one the whole I think it works really well.

Eleaf iJust 21700 Kit


The Ello Duro comes with 2 different mesh coils.

Eleaf refers to them as either a net coil (HW-N) or multihole coil (HW-M).

Each coil has a 0.2-ohm resistance and utilizes a Kanthal mesh material. One is called the HW-N2 (net coil) and the other HW-M2 (multihole coil).

These are the second generation Mesh coils to come with the Ello tanks, hence the number 2 after each coil name.

The HW-N2 has the finer course mesh amongst the two and does heat a little faster than the HW-M2.

The Ello Dura is also compatible with any of Eleaf’s Ello coil range along with being compatible with Smok’s baby beast coils.

Eleaf iJust 21700 Kit

Starting with the iJust 21700 device itself there’s not much to complain about.

It’s a simple power output device that is pretty dependant on the batteries that you are using inside.

That being said, it does seem to fire relatively fast, and using the included avatar controls 21700 battery, it seemed pretty efficient.

I also tried a Samsung 40T battery inside, and there wasn’t much noticeable difference.

Eleaf iJust 21700 Kit

However, irrelevant of which battery you use inside I really feel like the new mesh coils that come with the Ello Dura are left a little shy.

Let me explain.

The HW-M2 0.2-ohm mesh coil is rated for 40-90W, and the HW-N2 0.2-ohm mesh is rated for 40-90W.

Both a pretty decent Mesh coils, not the best on the market but as you’d expect from Eleaf – above average.

However, they perform best when they are in the 65-70W range, in my opinion, and with the direct power output of the device, you won’t be able to achieve that range for too long.

Eleaf iJust 21700 Kit

When I slapped the Ello Dura on top of my Innokin Proton with its regulated performance, I had a much better experience, and actually, think it’s one of Eleaf’s best tank/coil combinations to date.

Unfortunately, that just isn’t always the case with the iJust 21700 mod. It’s not to say either is bad, but maybe they’re just not the perfect marriage.

On a positive note, there are a plethora of Eleaf coils that can be used with the Dura and some I feel may lead to an extended enjoyment of the iJust 21700 kit as a whole.

Good Vibes

      • Stylish design
      • Good build quality
      • Feels good in the hand
      • Instant firing
      • Decent battery life
      • Fits 25 mm atomizers
      • AFC is easy to adjust and smooth
      • Two glass options
      • Good top-fill system (with safety lock)
      • 1 Amp charging
      • Passthrough vaping
      • Included 21700 battery in the kit

Bad Vibes

      • Device can’t power the included coils optimally
      • Battery LED indicator could be better
Eleaf iJust 21700 Kit


The iJust 21700 kit is much like many other iJust devices to come before it. It’s well built, looks nice as a complete kit, and comes with a decent sub-ohm tank.

On the performance front, it does a fairly solid job. But due to the nature of the device without a fully regulated board, it lacks the necessary oomph to make the most of the new N2 & M2 mesh coils.

The coils themselves produce good flavor, maybe the not the best on the market but still above average.

If you like the look of the iJust 21700 kit, you might be better off getting some different Eleaf coils.




There's nothing inherently wrong with all the pieces of the iJust 21700 kit, in fact, they are pretty good. I think the Ello Dura tank and new M2 & N2 mesh coils are Eleaf's best yet - Sadly, there just isn't enough power from the direct power output 21700 to make the most of those coils.
Jules Martinez
Jules Martinez
Jules Martinez, co-founder and Editor-in-Chief of our vaping site, brings a decade of expertise in vaping, CBD, and cannabis. His comprehensive knowledge and editorial rigor ensure high-quality, accurate content, positioning us as a trusted resource in the community.
CBDfx Gummies High-Potency 1500MG CBD

Related Articles

Best Vapes

Learn More About Vaping

There's nothing inherently wrong with all the pieces of the iJust 21700 kit, in fact, they are pretty good. I think the Ello Dura tank and new M2 & N2 mesh coils are Eleaf's best yet - Sadly, there just isn't enough power from the direct power output 21700 to make the most of those coils.Eleaf iJust 21700 Kit | Review