The CUBIS BF Coil Sub-ohm TC Tank is the latest tank platform of the highly raved Joyetech family, focus on providing a functional yet stylistic package that implements an innovative first-of-its-kind cup design tank reservoir, independent top-fill juice control with 3.5mL capacity, optional e-juice container transformation, elegantly integrated hidden top airflow control, and the utilization of Joyetech's latest varied BF Coil Structure. The CUBIS Tank's cup design allows simple coil replacement and juice refills by removing the top cap from the tube. This ingenious invention can only achieved by engineering the atomizer core to the top cap, versus at the bottom base near the 510 thread of the traditional tank system. Thus, top-filled method has never been more convenient, easily by unscrewing the top cap base from the tube to expose the e-liquid chamber slot with No-Spill capability. By removing the top cap base, you can transform the CUBIS Tank into a liquid container with secure storing and carrying by attaching a specially designed atomizer cap to the tank reservoir. Integrated within the top base is a hidden airflow control vent that is elegant for an unified and aesthetically pleasing look. This entirely new tank assembly greatly reduces leakage and coil flooding, with detachable and washable structure that makes it easier and more efficient to operate. The introduction of the BF Coil Structure (Bottom-Feeding) is the advancement of Joyetech's proud eGo One CL atomizers, customized specifically for the CUBIS Tank. It applies Bottom-Feeding apparatus with dual e-juice inlets which essentially eliminates coil leakage due to the new tank platform. The BF Coil Structure adopts a variety of coil configurations and heating elements to be utilized with a wide variety of output devices and supporting different types of vaping methods: mouth inhale or direct lung inhale. Manufactured out of high-quality Stainless Steel and built with multitudes of innovative functionality, the CUBIS BF Coil Sub-Ohm TC Tank is set to be the ultimate all-day flagship tank from an illustrious franchise.