What Are Prefilled Pod Systems And How Do They Work
What Are
Pod Systems?
The most common vape format in the UK since June 2025. Rechargeable body plus a 2ml pod. Here is exactly what it is, what is inside it, how it works mechanically and why the format looks the way it does.
A prefilled pod system is a compact vape device with a rechargeable main body plus a replaceable 2ml pod containing nicotine e-liquid. When you draw on the mouthpiece a sensor activates the battery which heats a small coil inside the pod. The coil vaporises the e-liquid which is inhaled into the lungs where the nicotine is absorbed into the bloodstream. The main device lasts one to three years. Only the 2ml pod gets replaced as a consumable.
What is inside
and how fast it works
Three numbers that between them summarise the full pod system in consumer terms. Ingredients, capacity plus speed.
In the e-liquid
Propylene glycol, vegetable glycerine, flavourings plus nicotine salt. Four regulated ingredients. Nothing else.
UK TPD limit
Every compliant UK pod is capped at 2ml of e-liquid which delivers approximately 600 puffs at standard draw length.
Full cycle time
Sensor to vapour in under a second. No button press required on most modern pod devices. Fully automatic.
Four components, four ingredients plus a draw-activated coil
A prefilled pod system is the most common type of vape device in the UK since June 2025. It is what most smokers switch to when moving away from cigarettes. It is what most former disposable users moved to after the single-use ban. Despite its prevalence the way a pod system actually works is not widely understood. Here is the full explanation covering what the device is, what is inside it, how the nicotine gets to you and why UK regulators designed the format the way they did.
The component breakdown
A modern pod kit is made up of four component groups. Each has a specific function and a specific lifespan.
- The main device. This is the body you hold. Inside sits a rechargeable lithium battery, a small circuit board including a draw sensor, a USB-C charging port plus the electrical contacts that connect to the pod. The device lasts one to three years of daily use.
- The pod. A small 2ml plastic cassette containing the e-liquid plus the heating coil. The pod is the consumable element. It lasts days (pre-filled) or a few weeks (refillable) before replacement.
- The coil plus wick. Inside every pod sits a small electrical heating element wrapped in cotton wick. The wick draws e-liquid from the 2ml reservoir up to the coil. The coil heats rapidly to vaporise the liquid when you draw on the mouthpiece.
- The USB-C cable. Supplied with every new kit. Standard USB-C compatible with most modern phone cables as a replacement.
What is in the e-liquid
UK-compliant pod e-liquid contains four ingredients. That is it. Nothing else is present in meaningful quantities.
- Propylene glycol (PG). A colourless liquid used widely in pharmaceuticals and food. Carries flavour well and produces a satisfying throat hit. Roughly 50 per cent of a typical pod liquid.
- Vegetable glycerine (VG). A thicker sweet liquid derived from vegetable oils. Creates vapour volume. The other 50 per cent of a typical 50/50 pod liquid.
- Food-grade flavourings. Small quantities of approved flavour compounds. Present at roughly 5 to 10 per cent of total volume.
- Nicotine salt. The active ingredient. Capped at 20mg per millilitre under UK TPD 2016 law. Absorbed fast into the bloodstream via the lungs.
How the device actually works
The mechanical process is simpler than most users realise. When you draw on the mouthpiece a small pressure sensor inside the device detects the change in air flow. That signal closes the circuit between the battery and the pod coil. The battery then delivers electrical current to the coil which heats to vaporising temperature in under a second. The heat vaporises e-liquid wicked up from the pod reservoir by the cotton wick. The resulting vapour travels up through the mouthpiece into your mouth plus lungs. When you stop drawing the sensor disengages the circuit and the coil cools instantly. The whole cycle takes under a second.
Some older pod kits used a button to fire the coil manually. Almost every modern device uses automatic draw-activation which feels closer to a cigarette plus removes one step from the user experience.
How nicotine reaches your bloodstream
The vapour you inhale is not smoke. There is no combustion. The liquid is heated to roughly 200 degrees which is well below the 700+ degrees tobacco burns at. That temperature difference is the key distinction that makes vaping less harmful than smoking. No combustion means no tar, no carbon monoxide and none of the 7000+ chemicals produced by burning tobacco.
Once inhaled the nicotine salt vapour enters the lungs where the fine alveolar surface rapidly absorbs it into the bloodstream. From there nicotine reaches the brain in roughly 10 to 20 seconds. The nic salt formulation specifically is designed to replicate the absorption curve of a cigarette which is why pod systems work well as a smoking substitute. Older freebase e-liquid absorbed more slowly plus felt harsher at the same strength.
Why the format exists in this specific shape
The 2ml cap, the 20mg nicotine ceiling plus the rechargeable refillable design are all regulatory outcomes rather than engineering choices. The 2ml cap comes from UK TPD 2016. The 20mg cap comes from the same regulation. The rechargeable refillable requirement comes from the Environmental Protection (Single-use Vapes) Regulations 2024 which banned non-compliant formats in June 2025. Pod systems exist in the specific shape they do because UK regulators wanted a product that could replace cigarettes for adult smokers without the environmental waste of disposables or the excessive nicotine of unregulated formats.
Pre-filled pods vs refillable pods
Modern pod systems come in two sub-formats. Pre-filled pod kits use disposable 2ml pods that come sealed from the factory with the liquid already inside. When empty you swap in a fresh pod. Refillable pod kits use reusable 2ml pods with a silicone fill-port cap that you refill from a 10ml nic salt bottle. Pre-filled is more convenient. Refillable is cheaper per ml plus lets you pick any brand of nic salt. Both are equally legal.
If you are ready to try a pod kit our pod vape kits collection covers every major UK brand in both pre-filled plus refillable formats.
What sits inside every
UK compliant pod kit
A pod kit looks simple from the outside because the engineering sits inside four neat components. Here is what each one does.
Main device
Rechargeable lithium battery, draw sensor plus USB-C port. Lasts one to three years of daily use.
Pod
2ml plastic cassette holding the e-liquid, the coil and the cotton wick. The consumable element.
Coil plus wick
Small heating element inside each pod. Cotton wick draws liquid to the coil for vaporisation.
USB-C cable
Standard charging lead shipped with every new kit. Compatible with most modern phone cables.
The core
of the pod system
Four-ingredient e-liquid
PG, VG, flavourings plus nic salt. Nothing else in meaningful quantities. Fully regulated under TPD 2016.
Draw activates the coil
A pressure sensor detects airflow and closes the circuit. Current heats the coil which vaporises the e-liquid. Under one second per cycle.
No combustion
E-liquid is heated to around 200 degrees. Cigarettes burn at over 700. No tar, no carbon monoxide, no combustion by-products.
Rechargeable plus refillable
Main device lasts years. Only the 2ml pod is replaced over time. Fully compliant with the June 2025 UK ban.
Shop the pod kit range
Our pod vape kits collection covers every major UK-compliant brand in both pre-filled plus refillable formats. Elf Bar, Lost Mary, SKE Crystal, IVG plus Hayati. Free next-day delivery on orders over £20.
What a UK pod kit is
versus what it is not
Pod systems are defined by a specific set of features under UK regulation. Here is the quick side-by-side of what makes something a compliant pod kit versus what falls outside the category.
Compliant UK pod kit
- ✓Rechargeable battery lasting one to three years of daily use.
- ✓2ml UK-compliant pod capped under TPD 2016 rules.
- ✓Nic salt e-liquid at 20mg maximum for fast craving relief.
- ✓Mouth-to-lung draw matching the cigarette style familiar to ex-smokers.
- ✓Automatic draw activation no button to press on most modern kits.
- ✓MHRA-notified product verifiable on the public register.
Outside the category
- ✗Single-use disposables banned since 1 June 2025.
- ✗Pod capacity above 2ml outside UK legal rules.
- ✗Nicotine above 20mg per ml non-compliant for UK retail.
- ✗High-VG shortfill liquid for sub-ohm mods not pod kits.
- ✗Direct-to-lung draw style unfamiliar to ex-smokers.
- ✗Manual-button firing only adds an extra step versus draw-activated.
For the wider view on everything pod-system related including safety, longevity plus switching from smoking, our prefilled pod systems guide brings every chapter together.
Back to the Prefilled Pod Systems guide
This article is one chapter inside our complete Prefilled Pod Systems knowledge base. Head back to the hub for the full index covering refilling, safety, longevity plus regulation.
More on pod kits as a starting point
For smokers evaluating whether to switch, our piece on are prefilled pod systems better for quitting smoking covers the evidence from the NHS and OHID. Once you are ready to pick your first kit, what to look for when choosing a prefilled pod system walks through the features worth prioritising. And for day-to-day care of any pod kit, how to use prefilled pod systems safely covers the practical habits.