Innokin Endura S1 Vape Kit

The name's a bit confusing at first glance. Refillable disposable. Those two words don't usually sit next to each other, and that's sort of the whole point of the S1.

What Innokin have done here is take the format people already understand — that slim, tube-shaped disposable vape — and made it refillable. Same size, similar feel in the hand, same inhale-activated firing. But instead of throwing it away when the liquid runs out, you just top it up from a 10ml bottle and carry on. The coil is built in so you're not swapping anything out. Just fill, vape, fill again, until the battery eventually gives up after around 7,000 puffs. Then you replace the whole device.

It sounds obvious when you say it out loud. And yet hardly anyone was doing it at this price.

What You're Actually Getting

The S1 is a slim cylinder, 18.5mm wide and 101mm long. That's about the size of a standard pen. Lighter than most phone cases. Fits properly in a jeans pocket rather than just technically fitting. It runs on a 650mAh battery at a fixed 13.5W output, which is a sensible wattage for the 0.8 ohm mesh KAL coil inside. You don't adjust anything. You don't need to

The 2ml tank is TPD compliant, which means it works with standard UK 10ml nic salt bottles. Fill it, let it sit for a minute, then you're vaping. No tools, no coil swapping, no priming ritual beyond just waiting for the cotton to saturate.

USB-C charging at the bottom. Same cable as your phone, most likely.

Box contains the device and a manual. That's it.

Who Is This For

Honestly, a few different types of person end up landing on the S1.

There's the smoker who's just switched and finds pod kits a bit overwhelming. The S1 looks familiar, behaves familiarly, doesn't require reading a manual properly. It just fires when you inhale.

Then there's the disposable vaper who's done the maths and realised they're spending £8-10 a week on single-use bars. The S1 flips that. At £5.99 for the device, then maybe £2-3 per 10ml nic salt bottle giving roughly 600-700 puffs, the ongoing cost is considerably lower. Especially if you're buying 4 for £10 nic salts.

And there's the person who wants something genuinely minimal. No wattage settings, no screens, no modes. Just a refillable vape that works without thinking about it.

The Refilling Part

The S1 has a silicone-sealed fill port, usually on the side or base depending on the exact variant. You squeeze liquid in from a 10ml bottle, seat the seal back, give it 60 seconds, and vape. The 2ml capacity doesn't sound like much but at 13.5W you're not burning through liquid at sub-ohm speeds. It lasts a reasonable session.

One thing worth knowing: the S1 is designed for 50/50 liquids and nic salts. The 0.8 ohm coil and the wicking channels are sized for those thinner liquids. High VG shortfills are too thick and will wick slowly, leading to dry hits. Stick to 10ml nic salts or 50/50 e-liquids and you'll be fine.

The Mesh Coil

The 0.8 ohm KAL mesh coil in the S1 sits between what you'd call a pure MTL and a restricted DTL draw. It's not as tight as the T18E coil in the Endura M18. There's a bit more airflow, a slightly warmer hit. Some people coming from disposables actually prefer this because it's closer to what they're used to.

The mesh design helps with consistency. Mesh heats more evenly than wire, which means flavour stays cleaner for longer. You're not going to get a degraded vape halfway through the device's life if you're filling with decent nic salts.

Because the coil is built in rather than replaceable, the device is designed to last until the battery degrades, then you replace the whole thing. For most people at normal usage that's several weeks of vaping.

The 7,000 Puff Claim

Worth a brief mention because puff counts are always optimistic. 7,000 puffs is the manufacturer's figure based on short, controlled draws. Real-world usage varies considerably depending on how long your draws are, how often you chain vape, and how you store it. Most vapers find these estimates run 20-30% high in normal use. Still, it's considerably more than a disposable bar, and the cost-per-puff works out very favourably compared to most alternatives.

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