Cleito Tank by Aspire Down the center of each Sub-Ohm tank exists a chimney, usually made of stainless steel, that is meant to channel the vapor from your coil through the tank and into your lungs. What Aspire did with this tank is essentially completely eliminate the chimney portion, while still allowing for the vapor to get to your lungs. The coils inside the tank are threaded into the base where the airflow exists, and are stretched throughout the whole system and threaded to the top of the tank! Their structure is meant to bring out the most prominent flavor possible by bringing the vapor into your lungs directly from the heating element. In addition, this increased amount of air that goes over coil causes for an increase in cloud production and density!