The concentric stainless butterfly valve is designed primarily for flow control and regulation of corrosive media, especially various kinds of strong acids, such as sulfuric acid and aqua regia.

The stainless disc of the butterfly valve is positioned in the center of the pipe; passing through the disc is a rod connected to an actuator on the outside of the valve. Rotating the actuator turns the disc of the stainless butterfly valve either parallel or perpendicular to the flow. 

As a whole, the stainless butterfly valves are used in applications which require higher resistance against corrosion.

Usuall they come with PTFE seal material which will not pollute media within a pipeline.
The stainless butterfly valves can be used in lot of applications and industries as chemical, beverage, brewing, pharmacy, petroleum refining,  ultrapure water, paper, mining, nuclear power, irrigation and other industries.