Innokin Prism T20S Tank Kit, 7 Colour Options, from £36

The 0.8 Ohm Prism T coil is the higher-power option. At sub-ohm or near-sub-ohm resistance, this coil draws more current and heats more e-liquid surface per firing. The result is a warmer draw with more vapour production -- suited to vapers who prefer a direct-to-lung style with a restricted airflow. At 0.8 Ohm, the output is moderate rather than extreme, making it accessible to vapers moving from a standard pen device rather than requiring the higher-wattage mods that true sub-ohm coils demand.

The 1.5 Ohm Prism S coil is the higher-resistance alternative. Running at lower wattage, it produces less vapour and delivers a tighter draw that closely resembles a cigarette pull. This is the coil recommended for vapers who are switching from smoking and want the most cigarette-like experience from the T20S. The 1.5 Ohm is also the more economical coil in terms of e-liquid consumption: the lower power means liquid is vaporised more slowly, so each coil lasts longer and each bottle of e-liquid goes further.

Swapping between the two is straightforward. Remove the base of the tank, unscrew the fitted coil, thread in the replacement, reassemble, and prime the new coil with a few drops of e-liquid before refilling. Having both resistances in the box means you can try the 0.8 Ohm first and switch to the 1.5 Ohm if you prefer a tighter draw without a separate purchase.

Innokin's Prism tank series covers several diameter and coil specifications. The T20S is a 20mm form-factor tank, which places it at a different point from the 18mm T18 series. The wider body of the T20S gives a larger e-liquid reservoir and slightly more room for the coil assembly, which is part of why it can accommodate the higher-power 0.8 Ohm coil alongside the 1.5 Ohm MTL option.

If you are deciding between the T20S and the T18E or T18-II in the range, the key distinction is the coil weight and device pairing. The T18 series tanks are built around a tighter form factor and typically pair with slimmer pen-style devices. The T20S is better suited to a boxmod or a wider pen device where the 20mm base sits flush with the device body. The dual coil kit format of the T20S also makes it the more versatile starter option -- you are not locked into a single vaping style when you unbox it.

All seven colour options are available: Black is the default and the most understated choice for vapers who want the tank to blend with their device. Silver is the clean, neutral alternative that pairs well with stainless-steel or chrome device finishes. Red, Blue, and Purple give the tank a bolder single-colour statement without drawing attention in the same way the Rainbow finish does.

The Rainbow T20S uses a multicolour anodised finish that shifts between colours depending on the light angle. It is the most visually distinctive option in the range and a common choice among vapers who want their equipment to stand out. Gray is the muted alternative for those who want something other than Black but prefer a lower-key finish over the brighter colour options.

The tank arrives with the 0.8 Ohm coil already fitted, so the only real discipline is priming before the first vape. Skip that and the cotton scorches on the opening draw, which is the most common reason a brand-new tank tastes burnt. The same applies the day you swap in the 1.5 Ohm spare.