The Aspire Zelos 50W 2.0 kit is a new release to include the brand new Aspire Nautilus 2S Tank. The new Nautilus 2S which comes with a DTL 0.4ohm coil and a 1.8 BVC MTL coil. A new airflow slot on the tank gives the additional airflow required for the DTL coil. If using in MTL mode the small airflow inlets can be selected. The top cap has a lift up and slide child proof mechanism and you can fill this from the top.