Crown IV Tank is the upgraded version of Crown 3 which was one of the hottest sellers in the the vape market. Constructed by SS & Pyrex Glass, the Crown IV looks durable and gorgeous. With a bubble pyrex glass tube in the package, the tank can hold a 6ml large capacity of e-juice (5ml in the normal tube). The biggest highlight of the Crown IV is the advanced patented self-cleaning technology, the Uwell Crown IV can absorb the e-juice in the condensation holder through regular usage and vaporise it. Moreover, the Dual SS904L coil and Double helix mesh coil is available on the tank, which will achieve heating evenly and produce excellent flavor. With the top filling design and bottom adjustable airflow system, you can enjoy an easier refilling method and smooth airflow.