Vape Pen Guide | How Pen Kits Work and Who They Suit

Browse any UK vape shop online and the vape pen has a whole section to itself, usually wedged between the pods and the box mods. Product listings stack up milliamp-hours and ohms, and almost never explain them. Behind the simple, slender shape sit several quite different devices, and some of them are a poor match for a first purchase. Here are the most common questions, with short answers.

What is a vape pen?

A vape pen is a cylindrical device, roughly the size of a chunky pen, that combines a battery with an e-liquid tank fitted with a coil. It runs on a single button, with no screen and no wattage setting to adjust.

Two classic examples, the Aspire PockeX and the Joyetech eGo AIO, share almost the same footprint according to their manufacturers. They measure 19.7mm and 19mm across respectively and are about 118mm long, each with a built-in 1500mAh battery and a 2ml tank.

Vape pen, AIO, pen kit, cigalike, what is the difference?

Shops use these words almost interchangeably, yet they describe different objects, and the distinction matters when you buy a replacement part or coil.

The AIO pen, all in one

AIO stands for All In One. The tank sits inside the body of the device and does not come apart from the battery, so the coil is the only part you replace regularly. Joyetech describes its eGo AIO in exactly those terms, with the atomiser housed inside the tube. In a sense, this kind of kit is the ancestor of the pod.

The pen kit with a screw-on tank

Other models, sold as pen kits or tube kits, join two separate parts, a cylindrical battery and a tank screwed on top. The tank holds the e-liquid and the coil. Like the AIO, a pen kit of this type runs at a fixed output and has no screen.

The cigalike

A cigalike copies the size and shape of a cigarette, with a cartridge or a very small tank. Its smaller battery gives it less running time. A pen therefore sits a step above it, both in capacity and in time between charges.

Does a vape pen have any settings?

No electronic settings at all, and that is the whole point. A standard vape pen does not let you choose the wattage and offers neither a menu nor temperature control. The only technical choice is the coil, whose resistance shapes the result.

Firing usually means holding a button while you inhale. Some models activate automatically when you draw on them, with no button at all.

The Aspire PockeX uses what the maker calls a bypass output, which means the coil receives the battery voltage directly, without electronic regulation of the power. The chip still keeps its protections against short circuits, overheating, overcharging and over-discharge.

Vape pen or pod, which should you start with?

For a first device, a pod wins in most cases today. Recent pods have largely replaced AIO pens thanks to their simplicity, while adding a few settings, and they sit between the pen and the box mod.

The pen is still often among the cheapest kits to buy, and its metal body, stainless steel on the PockeX, is described by Aspire as solid and built for life on the move. Its clear glass tank shows the e-liquid level at a glance, which helps you avoid dry hits.

A pod suits anyone who wants something compact and recent with a little adjustment. A vape pen makes sense for anyone who wants no settings whatsoever, a sturdy body, a replaceable coil and a tank they can read.

Which e-liquid suits a pen?

Start with the coil fitted. Aspire supplies the PockeX with two options, a 0.6 ohm coil in 316L stainless steel, built for flavour and vapour alike, and a 1.2 ohm Kanthal coil that the manufacturer recommends for e-liquids with a high nicotine strength.

Your inhale style matters too. With a mouth-to-lung draw, the vapour is held in the mouth before it reaches the lungs. With a direct-to-lung draw, it goes straight down. A lower resistance and a more open airflow point towards direct-to-lung vaping and a liquid richer in vegetable glycerine.

Sweet dessert recipes gum up these small coils faster, a point covered in detail in our guide to caramel flavour e-liquid.

Under UK rules, as summarised in MHRA guidance on GOV.UK, nicotine e-cigarette tanks are restricted to 2ml, a single refill container of nicotine e-liquid to 10ml, and nicotine strength to 20mg/ml. The two pens mentioned above both list a 2ml tank, which is exactly the legal ceiling for a nicotine tank.

How long does the battery last and how do you charge it?

The battery is built in, so you charge the device itself through its USB cable, with no external charger needed. The PockeX charges over USB-C, while early batches used micro-USB. The eGo AIO plugs into a computer or a wall adaptor with a 5V output.

With 1500mAh on board, real running time depends mostly on the coil you fit. On a bypass device such as the PockeX, the coil receives the same voltage whatever its resistance, so a 0.6 ohm coil draws twice the current of a 1.2 ohm coil and drains the battery faster.

Removable cells and their charger only matter for tubes without a built-in battery, such as a mechanical mod.

Is a mechanical tube mod the same thing?

No. A mechanical tube mod looks the same from the outside, but it works purely mechanically, without the protection chip of an AIO pen. It is aimed at experienced vapers, because using one safely means understanding Ohm’s law and matching the coil build, the power and the discharge rating of the cell.

That discharge rating is a key idea, explained in our guide to the 21700 battery. For a first device, the only sensible answer remains an AIO pen or a pod, protected by its own electronics.

How do you clean a pen and when should you change the coil?

Looking after a pen takes a few simple steps, mostly when you change the coil. Two moments deserve attention, cleaning the right parts and spotting a worn coil.

Cleaning the right parts

The drip tip, the mouthpiece you put to your lips, comes first. Rinse the tank each time you change the coil, with the coil removed beforehand. The base of the tank and its threads, which connect every part together, need a wipe as well.

Knowing when to change the coil

A worn coil gives itself away with three signs, a burnt taste, e-liquid leaking and thinner vapour. How long it lasts depends mostly on the liquid you use, as our guide to Geekvape coils explains, even though every pen maker uses its own coil references.

FAQ

Five practical questions that tend to come up once the pen is in your hand.

How long should you wait before using a new coil?

Aspire advises letting the cotton soak up e-liquid for around two to three minutes, depending on how thick the liquid is, before firing for the first time. Joyetech suggests dripping a few drops straight onto the coil before first use. Both steps aim to stop the cotton burning while dry.

How do you stop a pen from leaking?

Avoid filling the tank to the brim, as Joyetech points out for the eGo AIO, so that nothing overflows when you put it back together. On the PockeX, filling from the top by unscrewing the top cap is designed to limit leaks.

How do you switch a pen off before putting it in a bag?

Five presses of the button switch the device off, and five more switch it back on. The PockeX and the eGo AIO both work this way. A pen that is switched off will not fire by accident at the bottom of a pocket.

What does the colour of the light mean?

On the PockeX, a blue light means more than 30 percent battery and a red light means less than 30 percent. On the eGo AIO, the light colour can be chosen from seven shades, and it goes out once charging is complete.

Can you adjust the draw on a pen?

Yes, on some models. The eGo AIO has an airflow ring on its cap, fully open when the two marks line up and closed down to the minimum after a quarter turn. Aspire highlights a wider top airflow and a wider drip tip on the PockeX, both intended for more vapour.

Choosing a vape pen, the essentials

A pen comes down to a cylindrical battery, a 2ml tank and a button, with no electronic settings. The AIO builds the tank into the body, the pen kit screws a tank on top, and the mechanical mod shares nothing with them but the shape.

The choice rests on the coil, lower for vapour and higher for a strong nicotine liquid, then on simple but regular upkeep. Next to a pod, a vape pen keeps the edge on sturdiness and on a tank you can read, and it remains a clear way into the wider world of vaping hardware, alongside pods and box mods.

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Editorial content for adult readers only. Vaping products contain nicotine, which is a highly addictive substance. Nicotine vaping products are not for sale to anyone under 18 in the UK. This article is not a purchase recommendation.