iStick is an newly launched battery with a fashionable metallic appearance, the highlight being the incremental OLED screen. This unit does not come with a tank and we highly suggest adding one after selecting a color.Capacity: 2200mAhThread Type: 510 ThreadFeatures:1. OLED screen: Its particularity lies in the incremental OLED screen displaying battery condition, resistance, wattage and voltage.2. 2200mAh large capacity:3. 20w strong output wattage: The output wattage can be up to 20w.4. Adjustable voltage: The voltage is adjustable vary from 3.0V to 5.5V.Switch the VV/VW mode:Press the square button for three times to switch the VV/VW mode when the battery is turned on.Charging:iStick is charged through USB port at the bottom.iStick supports charging with 1A wall adapter which is more fast.