A four-way ball valve is a type of multi-way ball valve that has four ports, allowing for the flow of fluid to be redirected in four different directions. It is typically made from stainless steel and has a ball inside with four holes that can be aligned with different ports to control the flow of fluid.

A common configuration for a four-way ball valve is the X-port configuration. In this configuration, the valve has one inlet port and three outlet ports, with each outlet port being at a 90-degree angle to the others. This allows the flow of fluid to be directed to any of the three outlet ports or to be stopped completely.

Four-way ball valves are commonly used in applications where the flow of fluid needs to be redirected or controlled in four different directions, such as in chemical processing, oil and gas, and water treatment industries. They are also used in applications where space is limited and multiple valves would be impractical. These valves are known for their durability and reliability, making them a popular choice for many different industries.