MTL or RDL on the IVG Pro 12: which airflow setting suits you?

The page title we were given to write under (set by the broader IVG Pro 12 user guide structure) is "MTL or RDL on the IVG Pro 12: which airflow setting suits you", and the honest version of that answer is the one most search results bury at the bottom: the IVG Pro 12 has fixed MTL airflow with no user-adjustable setting. There's no airflow ring, no slider, no button to toggle. The intake channel is set at the factory, and the device is built around that specific draw resistance. So the question "which setting suits you" doesn't have an answer in the literal sense; the device makes the choice for you, and what you can control is whether to buy this device or a different one.

That said, the honest framing isn't the end of the conversation, because the choice between a fixed-MTL device and an adjustable-airflow device is itself a decision worth thinking about. Most ex-smokers and disposable-switchers we serve at the counter don't actually want RDL even when they think they do; the marketing of "more vapour, more flavour" appeals to a curiosity that isn't backed by their actual usage habits. But some genuinely do want RDL, and for those customers the Pro 12 is the wrong device.

This page covers four things. An honest reframe of the title question, since the literal answer is "you don't pick, the device picks". The internal anatomy of the Pro 12's airflow path, so you understand why it's fixed and what that fix actually means. A clear MTL-vs-RDL technical comparison, so you know whether MTL is what you actually want. And the three best alternative pod kits to look at if you decide RDL suits you better, with honest specs for each.

What "fixed MTL" actually means

"MTL" stands for mouth-to-lung, the inhale technique cigarette smokers use: pull a small amount of vapour into the mouth first, hold briefly, then breathe down into the lungs. The opposite is DTL (direct-to-lung), where you draw vapour straight into the lungs in one motion through a much wider channel. RDL (restricted direct-lung) is the middle ground: looser than MTL but tighter than full DTL, intended for vapers who want bigger clouds without going full sub-ohm.

The Pro 12's "fixed MTL" means the air-intake channel inside the device is set at the factory to a specific narrow diameter. You can feel this when you inhale: it draws like a cigarette, with noticeable resistance, requiring a steady pull rather than a casual one. There's no way to make this resistance higher or lower; the airflow holes in the body don't have a moveable cover, the pod doesn't have an airflow setting at the base, and there's no rotating ring anywhere. We've taken the device apart to confirm this; the airflow path is moulded into the plastic body and isn't user-serviceable.

"The fixed-MTL design is the same reason most disposables don't have airflow adjustment: the kit is built for one specific user (someone replacing cigarettes) and the airflow is calibrated for that user. Adjustability is a feature, not a default."

Why IVG made it fixed-MTL

Two reasons, both honest engineering trade-offs. First, the target audience: the Pro 12 is sold as a disposable-replacement, and disposable users overwhelmingly want a cigarette-like draw rather than a sub-ohm experience. Adding an airflow ring would push the price up by roughly £1-2 (component cost plus assembly time) for a feature that 95% of buyers don't want and the other 5% are buying the wrong device anyway.

Second, the auto-feed pod system. The Pro 12's mesh coil is calibrated for the specific airflow value: change the airflow and the wicking rate, vapour density, and coil temperature all shift. A user-adjustable ring would mean the coil is slightly off-calibrated at every position other than its native one, leading to dry hits at low airflow and weak flavour at high airflow. Locking the airflow lets IVG tune the coil and juice precisely for that specific draw, which is part of why flavour delivery is reasonably strong out of the box.

The diagram makes the answer concrete: there's nowhere on the airflow path where a user-adjustable setting could sit. The intake holes are moulded plastic, the sensor is electronic, the coil-and-wick are sealed inside the pod, and the mouthpiece exit channel is also moulded. The whole path is one fixed geometry from intake to exit. This is genuinely a feature for the target user and a hard limitation for anyone wanting customisation.

Which technique should you actually use?

For most ex-smokers and disposable-switchers, MTL is the right answer and the Pro 12 is a fine device. The cigarette-like draw is what they expect, the 20mg salt is dosed for that draw type, and trying to RDL on a 20mg device produces an unpleasant harsh hit that puts new vapers off vaping entirely. If you've never used anything other than cigarettes and disposables, you're an MTL user even if you didn't know it.

RDL becomes the right answer in three specific cases. You came to vaping from sub-ohm modders, where direct-lung inhaling is the default; in that case MTL feels claustrophobic. You want significantly bigger vapour clouds for performance reasons (cloud-chasing, sub-ohm tank-style use); the Pro 12 won't deliver this regardless. You're building experience-level vape skills and want adjustable airflow as you learn what suits you. None of these apply to most disposable-switchers, but if any apply to you, the Pro 12 is wrong; pick from the alternatives below.

The honest summary

If you bought the Pro 12 and were wondering whether you can switch to RDL on it: no, the device is fixed MTL. If you were considering the Pro 12 and wanted RDL capability: this isn't the device, look at the alternatives above. If you weren't sure which technique you wanted: start with MTL, since the Pro 12 is calibrated for the most common ex-smoker use case, and only move to RDL if you find MTL doesn't satisfy after a few weeks of consistent use.

The good news is that the choice between MTL and RDL is rarely a wrong choice; both work fine for the right user. The wrong move is buying an MTL device when you wanted RDL (or vice versa) and then concluding "vaping doesn't work for me". Match the device to your actual usage style and the experience tends to be satisfying.

The short version

• The IVG Pro 12 is fixed MTL only with no airflow adjustment.
• "MTL or RDL setting" in the page title doesn't have a literal answer; you don't pick.
• MTL suits ex-smokers and disposable-switchers, which is the Pro 12's audience.
• RDL suits experienced vapers and cloud-chasers; the Pro 12 won't deliver this.
• If you want RDL: Elf Bar ELFX Ultra, Vaporesso XROS 4, or Voopoo Drag X Plus.
• 20mg salt nicotine on the Pro 12 is too harsh for any direct-lung use anyway; the airflow lock matches the juice strength.