This Amazing tank by HorizenTech brings some real competition to the sub ohm tank market. The Duos Sub features massive airflow with its three large adjustable airflow holes at the bottom of the tank. The design of the coils are made to fit the premade Duos coils that come with the device but in a pinch or if you like TFV8 coils more, you can always throw those in and it will work like a charm. Now we all know the tank can perform but what if you have a green mod and the red glass doesn't match? Well the Duos has multi color glass options that you can replace with at any time. Color glass sold separate.