OBS Crius II Dual Coil RTA is a rebuildable tank atomizer with 25mm diameter. It also adopts easy top side refill, adjustable bottom airflow, detachable structure and high-tech Zirconia piece just like the original Crius II RTA. The new dual coil version supports dual coil building for intense flavor and violent vapor production. It has juice flow control function so that you can you use different PG/VG ratio e-liquids for better vaping experience.