What a THC cartridge actually is
A THC cartridge is a small glass tank of cannabis oil with a heating coil and a mouthpiece, screwed onto a separate battery. Almost every cart sold in the UK uses the 510 thread, an industry-standard screw fitting, which means any 510 battery will fit any 510 cart regardless of brand. Carts are sold as half-gram or full-gram, and the oil inside is what separates a five-pound cart from a thirty-pound one.
Oil types, in plain English
Distillate is cannabis oil stripped back to almost pure THC, then re-flavoured with terpenes. It is the cheapest to produce, the most consistent, and usually the strongest on paper, but the flavour comes from added terpenes rather than the plant.
Live resin is extracted from flower frozen at harvest, so it keeps the strain’s original terpene profile. It tastes closest to smoking the flower itself and tends to feel more strain-specific. It costs more and the oil is thicker, so it wants a slightly warmer battery setting.
Cured resin sits between the two: extracted from dried flower rather than frozen, cheaper than live resin, more character than distillate.
Rosin is solventless, pressed with heat and pressure alone. It is the choice if you would rather no solvent touched the product at any stage. It is also the most expensive per gram and the most temperature-sensitive.
Liquid diamonds means THCA crystals re-dissolved into a terpene-rich sauce. Very potent, very flavourful, and increasingly common in 2G carts and disposables.
Choosing a battery
A cart is only as good as the battery under it. Look for variable voltage rather than a single fixed setting: 2.4–2.8V suits thin distillate, while 3.0–3.4V is usually better for thick live resin or rosin. Start at the lowest setting and work up. If the vapour tastes burnt or harsh, the voltage is too high and you are scorching the coil, which ruins both the flavour and the rest of the cart. Preheat modes, usually a double-click, gently warm thick oil before you draw; they are worth having in winter.
How to store a cart so it lasts
Store carts upright, at room temperature, away from direct sun. Lying a cart on its side lets oil creep into the airway and is the most common cause of leaking and clogging. Heat thins the oil and makes leaks worse, so a car dashboard is the worst place you can leave one. If a cart clogs, a few gentle preheat cycles usually clear it; never apply a flame.
Full-gram or half-gram?
A full-gram cart is better value per gram and is the sensible default for regular use. A half-gram is the cheaper way to try a brand or a strain you do not know. If you find you are getting through a cart every few days, the 2G disposables are usually cheaper still per gram, at the cost of not being able to swap tanks.
Sensible use
Cannabis vapour is not harmless. Start with one short draw and wait several minutes before another; concentrated oil is far stronger than flower and the effect builds. Do not drive or operate machinery. If you have a heart condition, are pregnant or breastfeeding, or take prescription medication, speak to a doctor first. If a cart makes you cough persistently, tastes chemical, or causes chest tightness, stop using it. Cannabis is a controlled drug in the UK; the information here is provided for harm reduction and product understanding, and it is your responsibility to know the law where you are.
Where to go next
our full range of THC vape cartridges, ready-to-use disposable vapes and the concentrates those oils come from. Everything ships tracked and discreetly from the Dank THC Joint shop.