The YFTK Flash e- V4.5S+  RTA YFTK Rebuildable Tank Atomizer is constructed from 316 Stainless Steel in 23mm Diameter. The RTA comes with a 4.5ml E- capacity glass tank tube, 1 x air screw mounted seald, 1 x 1.2mm airflow insert, 1 x 1.4mm airflow insert, and 2 x 2.1mm airflow inserts (pre-installed). The RTA features dual post build deck and adjustable airflow for MTL .