battery-watt-hours / vaping-watts = vape-time-in-hours will be close as it is 97% efficient and you save power when the temp limit cuts in @SlickWilly
Thank you! BTW, I wanted to ask you a question. I'm working on my 1590A today, I'm going to start drilling and cutting the holes and openings for the board in the next few hours and I'm still torn on how high or low to set the board. I know it will look a little out of place but I'm liking the fire button very close to the top, about half an inch down from the top. When this smaller box is in my hand I tend to set my index finger over the top and rest it on the base of the atty, this puts the mod lowest in my hand. That fills my hand with the bottom of the box equal to the bottom side of my hand and the fire button under the middle of my thumb pad, this is the same way I've held the istick's for so long it just feels right to me. How are you liking the spot where the fire button is on your's?