Pen vs cart: the parts
A vape pen is a battery, a switch, and a mouthpiece. A cart is a glass or plastic tank with a coil and a threaded base. The cart holds the oil. The pen supplies power. A disposable pen seals both parts into one unit and ships charged.
Threads decide fit. The 510 thread is the standard for carts. It measures about 7 mm across with a 0.5 mm pitch. A 510 cart from one brand fits a 510 battery from another. Pod systems break that rule. Pods use a snap or magnetic connector that fits one brand.
Pick first: disposable pen
Buy a disposable pen first if you own no battery and want one purchase. Numbers to expect: 0.3 mL to 1 mL of oil, 200 mAh to 400 mAh of battery, 100 to 300 puffs. Puff counts come from the seller. No independent body verifies them.
Trade-off: cost per milligram of CBD runs higher than a cart and battery bought apart. When the battery dies, the unit goes in the trash.
Pick second: 510 cart plus a battery
Buy a 510 cart and a separate battery for lower cost per milligram and more control. Battery capacity runs 350 mAh to 1100 mAh. Variable voltage models adjust from 2.5 V to 4.2 V. CBD distillate and live resin flow at 2.5 V to 3.5 V.
Heat above 3.5 V degrades terpenes and gives a harsh hit. Start at the low setting. Raise voltage in 0.1 V steps until vapor appears.
Cart hardware checks
- Capacity: 0.5 mL and 1 mL are the two sizes most brands sell.
- Coil: ceramic coils resist scorching. Cotton coils cost less and burn faster.
- Airflow: bottom airflow clogs less with thick oil.
- Preheat: a 5 second to 10 second preheat cycle clears a clog.
- Threads: confirm 510 before you pay.
What the label should show
- Total CBD in milligrams per cart, not just a percentage.
- Batch or lot number.
- A third-party lab report, called a COA, with a cannabinoid panel and a contaminant panel.
- Terpene source. Botanical terpenes are added after extraction. Cannabis-derived terpenes come from the plant.
- Volume in mL.
Cost per milligram
Compare price per 100 mg of CBD. Example: a 1 mL cart labeled 500 mg CBD at $40 works out to $8 per 100 mg. A 0.5 mL disposable labeled 250 mg CBD at $25 works out to $10 per 100 mg. Run the math on the CBD number in the lab report, not the number on the front of the box.
Label accuracy
A 2017 study in JAMA tested 84 CBD products sold online. About 26% held less CBD than the label stated. The FDA has not approved CBD as an ingredient in vaping products. No cart on the market carries FDA approval for vaping.
Safety record
CDC lab testing tied vitamin E acetate to the 2019 EVALI outbreak. Most case patients reported THC products, not CBD. Vitamin E acetate is a thickening agent. It has no place in a cart.
Buy order
- No battery, one purchase: one disposable pen, 0.5 mL.
- Own a 510 battery: one 1 mL cart with a COA.
- Want the lowest cost per 100 mg: one 510 cart plus a variable voltage battery.
- Vape often and want no refills: two carts and one spare battery.
Unknowns
Puff counts are seller estimates. Long term inhaled CBD data in humans is thin. If a cart tastes like plastic or burns your throat, stop and check the voltage setting.