Equipped with essential rubber components, this repair kit is designed for both checks and relief valves in plumbing backflow preventers. It includes seal rings, O-rings, a diaphragm, and a relief valve stem O-ring, ensuring a comprehensive solution for maintenance needs. The durable rubber materials provide reliable sealing and performance. Use caution when servicing, as the covers may have spring tension. This kit is a genuine Zurn product, ensuring compatibility and quality.