The Uwell Crown III is the newest model in the sub-ohm tank series. The Crown III has a 5mL juice capacity and a 24.5mm stainless steel base The Crown III has an upgraded chimney and structural design. There are several coil options for this tank including a 0.25 ? Stainless Steel 316 coil, and a 0.5 ? Kanthal coil. The airflow ring has also been adjusted in this model. The Uwell Crown III is definitely an upgrade from the previous models.