My work day is about 12 hours from the time I leave home until the time I walk back through the door. I take 2 mods and 2 atomizers with me along with e-liquid to fill up. The atomizers can be any mix of RTAs, RDAs, or sub ohm tanks. The mods can be any mix of parallel or series mech mods, or regulated mods. I have some Japanese organic cotton in my desk for re-wicking if necessary.