The Helios RDA Clone by Ehpro, is fully constructed of Stainless Steel. It features an inline triple post (tri-pole) coil mounting configuration with quad-pole functionality -- the center post has two separate mounting holes for easier installation of dual (or other multi) coil setups.
The Helios RDA Clone also features a built-in air flow control (AFC) in the cap with two holes on both sides. Air flow is controlled by adjusting the AFC ring, which uses a slotted opening for anywhere from one to both holes per side. The cap is secured to the base with dual o-rings, which makes for easy alignment of the air holes with the coils.