It looks like a clone of a Istick20. The internal battery isn't going to last long, I mean you'll be getting 6-8 months before you notice that its not holding charge as well as it use too. I go through a 18650 a day with my 1.4ohm provari that I take everywhere so its vaped all day. The lower the ohms of the coil and the higher the power you use the faster the battery gets drained. You are to expect @250-300 charges on a good battery, some internal batteries aren't of all that good of quality so less charging cycles before it fades.