A butterfly valve is a type of quarter-turn valve used to regulate the flow of fluid in a pipeline. It consists of a disc mounted on a rotating shaft, which can be turned a quarter turn to control the flow of the fluid. Butterfly valves are commonly used in various industries such as water treatment, HVAC systems, chemical processing, and oil and gas.

One of the key features of butterfly valves is their simple and compact design, making them easy to install and operate. They offer quick operation and require less space compared to other types of valves. Additionally, butterfly valves provide excellent flow control with minimal pressure drop across the valve. They are also known for their reliability and durability, making them suitable for a wide range of applications where throttling or isolation of flow is required.