The ELeaf IStick is designed with the OLED screen, the protruding adjustment buttons, as well as the fire button all on one side of the device. This makes using the iStick effortless since everything you need is at your fingertips. The easy to read high quality OLED screen displays the wattage, voltage, attached atomizer resistance, and battery level. The 2200 mAh capacity battery will last you all day long. Since the iStick boasts 20W of output wattage, you can create some of the biggest plumes of smoke possible. The adjustable voltage ranges from 3.0V- 5.5V, giving you the control to vape at your leisure.