The Ammit 25 RTA features 25mm diameter and can hold 2ml or 5ml liquid capacity. You can use an expansion adapter to enlarge it to 5ml. And it is also compatible with 810 drip tip. The new build deck makes single coil build easier and also supports larger coils. On the bottom of base, it has 3 different directions for bigger vapor production and nice flavor. This 3D airflow system will provide you prefect vaping experience.