This is a compact battery from eLeaf with a temperature control functionality is called the iStick 40w TC. It is one of the more affordable models on the market and works effectively. The temperature sensor will ensure that this does not happen and so you will be able to avoid the bad taste. It will allow vaping between 100 and 315 degrees C when you have it in temperature control mode and it works between 1 and 40w. It is a compact size and has a bigger battery capacity of 2600mAh which charges in 3.5 hours. Charging is a breeze with the included micro-USB cable.