Outfit your semi truck to be Ready for the Road Ahead with improved hydraulic flow regulation, with the Campbell 4" Cast Iron Body Butterfly Valve. Thanks to its ability to rotate a circular disc in a pipe, this replacement valve is the ideal solution to permit the flow of gases or fluids. Crafted with an ultra-durable nickel-plated disc to provide long-term reliability. FleetPride is your First Click in Heavy Duty .