I just want to make a point here, The atomizer is not the battery, the battery is just that, the battery, The tank or clearomizer is the Atomizer which is what you put the juice in, Then you screw the Atomizer Tank onto the battery, then sit down have a vape..lol ..Just wanted to put some humor into this, Then maybe tonight you can get the mAh of the battery, or check where you got it and they should be able to help you to find out. I would say it's a 650mAh just by the size of the battery, but being a Haus, it could be different.