The Green Smoke electronic cigarette is a cartridge based e cig. Meaning you use disposable cartridges rather than refilling with e liquid. The Green Smoke e cig has the appearance of a regular cigarette, complete with a light on the end that glows when a drag is taken. The Green Smoke e cig consists of two parts, the rechargeable battery and the cartomizer. A cartomizer is basically just an e liquid cartridge that also contains and atomizer. Each cartomizer is equal to about one and a half packs of cigarettes. I would have to say that I prefer the refillable types of ecigs vs the cartridge type. Just my two cents but I find it more convenient and way cheaper.