The 30mm Mason Dumptank RTA from Vapergate.
Built with both flavor and production in mind, the Dumptank offers a continually variable air flow control for completely closed off to a wide open draw. The Channeled juice holes allow the builder to position the wick without fear of the bell cap dislodging them. A generous 20mm deck offers plenty of space for anything from simple to advanced builds. Recommended build specs are 3.5mm-4mm or 9/64-5/32 coil diameter with medium snug wicking tension for best results.