The Nautilus GT is primed to be another magnificent addition to the Nautilus Family. Beautifully machined from top to bottom, this tank is compatible with all coils in the nautilus series. It is 24mm in diameter and holds 3.0mL of liquid with the standard glass. An extension accessory can be purchased to increase it to 4.2mL. The tank is filled via a twist and slide top cap, which reveals two filling slots. Unscrew the base hardware to access the coil deck which flows into 5 incrementally increasing airflow adjustments, clicking into place with each. From extremely restricted to tight DTL, this tank is truly an Mouth-to-Lung lover's dream!