# Electronic box: how to read a box mod spec sheet > What an electronic box spec sheet really says: output, cells, fitting, protections and resistance range, and the real use hiding behind each figure. Two devices both print 200 W and look identical on screen. One holds its stated output through a long session, the other sags after a handful of puffs. The answer was on the spec sheet, just not on the line everybody reads. On an **electronic box**, most of the printed values describe a theoretical component limit rather than everyday behaviour. The useful skill is knowing which lines to read, and in what order. ## What the spec sheet of an electronic box actually describes An **electronic box** spec sheet describes three separate things that marketing happily blends into one: what the circuit is willing to ask for, what the power source is able to supply, and what the chassis is able to take. Only the second one determines real runtime. Maximum output is a property of the chipset. Runtime and stability depend on the cells. Durability depends on the material and on the test standards claimed. The three blocks are independent, and a strong score on one never compensates for a weak score on another. In practice, the most useful line is almost never the wattage. It is the power source type, followed immediately by the resistance range the device will read. ## Stated output against output you can actually use The wattage figure is the one that sells, and it is also the one that misleads most. It states the ceiling the circuit accepts as a request, never the level the whole assembly can sustain over time. Two ceilings overlap here, and the lower of the two always wins. Chipset ceilings sort into readable tiers. Vaporesso quotes 5 to 220 W on the GEN 200 with two 18650 cells and 5 to 80 W on the GEN 80S with one, on its published spec sheets. Lost Vape quotes 5 to 200 W on the Centaurus M200, also on two 18650 cells, and 5 to 100 W on the Centaurus N100 with a single cell. The pattern repeats across every manufacturer: one cell for the hundred watt class, two cells beyond it. That is not a commercial convention, it is a current constraint, and it is the single most useful thing a wattage ceiling actually tells you. The cell ceiling is the one nobody prints. On a two cell device the cells sit in series, so the same current flows through both, and the assembly can only sustain what the weaker cell can sustain. A box that displays 220 W is not thereby a device with 220 usable watts. It is a device that will let you ask for them. That is why an **electronic box** rated at 220 W is not judged on its ceiling but on the wattage you actually run, which is set by the coil fitted rather than by the chassis. Almost nobody spends their day at the top of the dial. ## How to read a cell datasheet before you buy Since the interesting mods here take removable cells, and no manufacturer supplies them, this is the part of the purchase you are responsible for. The method matters, not a number copied from a forum thread. Work from the datasheet published by the company that actually manufactures the cell, not from the wrap it was rebranded under. Two lines carry the weight: the continuous discharge rating and the capacity. Both are quoted for stated test conditions, a temperature and a cut off voltage, and those conditions are part of the figure. Compare that rating against what your setup asks of it, and treat any demand that approaches the published rating as a reason to change the setup rather than to hope. On a series pair, the current is common to both cells, so the pair is only as capable as its weaker half. Four habits carry the rest. Buy and keep cells as a matched pair, same brand, same model, same age and same state of wear. Inspect the wrap before every insertion and rewrap at the first nick, because bare metal against a metal chassis is a direct short. Transport loose cells in a plastic case rather than a pocket. Charge on a charger designed for the format and chemistry, and retire any cell that has been dropped, has vented, or runs unusually warm. ## Removable cells or a built in battery This is the characteristic that shapes daily use, well ahead of looks. It decides runtime, weight, cost of ownership and the lifespan of the device. Two philosophies coexist and they do not target the same person. A removable cell charges outside the device and gets replaced when it ages. The Centaurus M200 runs on two 18650 cells, not supplied, at 3.0 to 4.2 V per cell according to Lost Vape. The Centaurus N100 accepts either a 21700 or an 18650, which lets you trade runtime against bulk in the same body. Vaporesso applies the same logic in the Armour Max, with two 21700 or 18650 cells for 5 to 220 W. The advantage shows over time: the electronics outlive the cells. A sealed body simplifies everything, at the cost of an obsolescence written by chemistry. The Armour Ultra carries 5500 mAh for 100 W, with charging quoted at 9 V 2 A or 5 V 3 A over Type-C. That is a rare capacity, aimed at heavy use with no cell handling at all. The compromise shows on the scales: 256 g for the complete kit and 173 g for the mod alone. A high capacity sealed **electronic box** always weighs more than a comparable device running on cells. ## Fitting, screen and resistance range These three lines usually sit below wattage on a product page, even though they decide whether the device works with the hardware you already own. A box that cannot take your existing atomiser is of no interest whatever its output. The 510 thread is the de facto standard on mods with a separate atomiser, so the point to watch is elsewhere: the maximum diameter without overhang. Lost Vape quotes a 26 mm wide chassis on the Centaurus M200, which frames atomisers up to 25 mm without visible overhang. The resistance range is the line that decides what the box will agree to fire. The Centaurus N100 reads from 0.1 to 3.0 ohm according to Lost Vape, which covers a sub ohm build and a tight mouth to lung coil alike. A range capped at 2 ohm rules out several recent mouth to lung coils. A range that stops at 0.1 ohm rules out the more aggressive rebuildable builds. ## Weight, format and physical robustness Dimensions and weight need reading in context, cells included or not. Lost Vape quotes 152 g for the Centaurus M200 without cells and 53 g for the Centaurus N100 without cell or atomiser, which completely changes how a comparison table reads. Some sheets add verifiable robustness standards. Vaporesso claims IP68 and IP69K on the Armour Ultra plus MIL-STD-810H, which covers a 1.2 m drop test among other things. That kind of claim can be checked, unlike a commercial adjective. ## Which electronic box for which use The table below crosses the characteristics above with concrete use, without trying to name a universal model. The right hand column is deliberately about the coil, since the coil sets the wattage rather than the other way round. | Dominant use | Power source to prioritise | Coil band usually fitted | |---|---|---| | Mouth to lung, out and about | Compact built in battery | Higher resistance mesh coils | | Mixed daily use | Single 18650 or 21700 cell | Mid range mesh coils | | Direct lung, larger vapour | Two 18650 or 21700 cells | Sub ohm mesh coils | | Rebuildable low resistance | Two cells, reading down to 0.1 ohm | Hand built coils | None of those uses lives near the ceiling printed on the box. What you actually run is dictated by the coil, a subject developed in our [Vaporesso GTX One kit guide](/uk/vaporesso-gtx-one-kit/), where the manufacturer ranges are set out ohm by ohm. One British specificity belongs here too. Refillable tanks sold in the United Kingdom are capped at 2 ml and nicotine containing e-liquid at 20 mg/ml in 10 ml bottles, so refill frequency is a real criterion on a high output setup, and it never appears on a wattage chart. ## Frequently asked questions ### Does a 200 W box use more e-liquid than an 80 W box? Not by itself. Consumption depends on the wattage actually set and on the coil fitted, not on the ceiling the device could reach. A 200 W box set to 25 W consumes exactly like an 80 W box set to 25 W. ### Can I use a single cell in a box designed for two? No. The two bays are wired in series and the circuit will not start with one missing. Putting a single cell into a dual bay is not a supported configuration and risks a short circuit. ### What does DIY or bypass mode do? It disables power regulation and passes the pack voltage straight to the atomiser, so the behaviour approaches a mechanical mod while keeping the electronic protections. It assumes the user already calculates the current their build will draw. ### Should I charge through the USB port or on an external charger? Both work when the box accepts internal charging. An external charger lets you follow each cell individually and balance an ageing pair, which internal charging does not always show you. ### How long does a regulated mod last? The electronics generally outlive the cells feeding them. On a removable cell device, replacing the cells extends the mod by years. On a sealed device, the end of the battery is the end of the product. ## Reading an electronic box spec sheet in the right order Start with the power source, continue with the resistance range, finish with the wattage. That reading order alone removes most bad purchases, because it puts the physical constraint ahead of the commercial argument. A well chosen **electronic box** is one whose three blocks of characteristics are consistent with each other and aligned on a defined use. The rest, finish, lighting effects, number of modes, is comfort and is judged in the hand rather than on paper. If you want to see that method applied to a specific family, our [Centaurus box mod guide](/uk/centaurus-box-mod/) walks through one range suffix by suffix, and our [Vaporesso box mod comparison](/uk/vaporesso-box-mod/) does the same across a second. Editorial content for adult readers only. Vaping products usually contain nicotine, a substance that causes addiction. Not for sale to under-18s in the United Kingdom. This article is not a buying recommendation.