A resilient seated gate valve is a type of valve commonly used in water distribution and wastewater systems to control the flow of water or other fluids. The primary feature of this valve is its resilient seat, which is typically made of elastomeric materials like rubber or synthetic compounds, designed to provide a tight, leak-free seal when the valve is closed. The valve consists of a gate (or wedge) that moves up and down within the valve body. When the gate is raised, it allows fluid to pass through the valve, and when it is lowered, the gate seals against the resilient seat to block the flow. The resilient seat ensures a superior sealing performance, especially in situations where there may be irregularities in the valve body or the gate. Resilient seated gate valves are known for their durability, ease of operation, and low maintenance. They are typically operated manually using a handwheel or automatically in more complex systems. 

Cast Iron Dual Plate Check Valve is a type of check valve designed to allow fluid (typically liquid or gas) to flow in only one direction and prevent backflow. The "dual plate" refers to the valve's internal mechanism, which consists of two hinged plates that open to allow fluid flow and close to prevent reverse flow. As a check valve, its primary function is to prevent backflow. The dual plates open when the flow is in the intended direction, and they automatically close when the flow reverses, preventing reverse flow or siphoning.