First off let me say that I am not an electrical expert, but do have enough vaping knowledge to not blow my face off. I have always wondered but can't seem to find a definitive answer online about what is the single most thing that determines battery drain rate on a regulated device (dual 18650). Resistance? Volts? Watts? Amps? In my experience, it seems that the lower the amp draw the better my battery life mo matter what resistance I build. Also, voltage doesn't seem to matter for batt drain so long as the amp draw is relatively low. I usually run my tfrta g4 (quad deck) with 20 wraps of 30 gauge kanthal, 1.25 ohms, 9v (max on the cuboid), and 7.5 amps. If I run a dual setup on a different tank at the same wattage, lower resistance, bigger wire or claptons, lower volts, and significantly higher amperage (12-17+amps), the battery drain is obviously considerably faster. Both types of builds yeild VERY similar cloud and flavor. For me, I can usually get any of my tanks to produce similar clouds and flavor by getting creative with smaller wire as opposed to throwing some big claptons or fused claptons. The trade off for better battery life by using smaller wire is well worth it in most cases. This is all assuming that AMPS is the main factor when talking battery drain. Idk, just trying to see what everybody's thoughts are......