25 ml Huge E-liquid Capacity: Compared with its previous generations, the Proteus Neo Tank capacity is upgraded to 25 ml to let you shisha worry-free and the convenient top fill design makes refilling a piece of cake without any leakage annoyance. Adjustable Top Airflow Fully adjustable airflow control gives you a completely customizable experience. You can choose the best airflow for your personal shisha style and the top dual airflow slots keep leakage to a minimum.