Twisted Messes and OhmBoy's Dang RDA sports an overall diameter of 24mm, and is constructed of 304 stainless steel. Additionally, it has a locking top cap, which not only properly positions the airflow, but makes it easy to take it on or off a device.
Speaking of airflow, it has a fully adjustable top airflow design, which means zero leaking and awesome flavor. What's even better is that there are honeycomb airflow slots, ensuring a smooth draw with each and every vape.