And each one has an independent button to control, but they share the same battery with a charging port. i would like to change the tank by putting four refill containers back in which attach to a large tank of the device. each container created contains 2 ml of liquor which will look like a round and long cartridge (therefore containers). the chosen liquids will either be mixed in a large tank inside and with resistance for four containers, or you will be able to consume the four containers at the same time through a system of mother connectors, or other systems linked to a button which turn on all the where reservoirs or activated each of the containers with their button. the concept is like a vape platform with four containers/bullets, these four containers can work separately.