Pre-filled THC oil cartridges are mini vape tanks filled with weed oil. These vape cartridges are sometimes referred to as hash oil, they contain concentrates like cannabis oil, distillates and even live resins. The tank contains a little curl which is controlled by either a standard weed pen battery or a 510 thread vape. These thc vape cartridges mostly contains 0.5 grams or 1 grams of thc oil that are extracted from weed plants. They are commonly useful for around 200-400 puffs.