The Mansfield 630‑0207‑12 Universal Flapper Kit includes a durable blue rubber flapper designed to fit 3-inch flush valves on Mansfield toilets, including their WaterSense models. Each kit comes complete with multiple inserts to ensure precise alignment over varying tank posts for a watertight seal. Constructed to OEM standards, this Mansfield-specific replacement delivers reliable performance and effortless installation, resolving common issues like phantom flushing or continuous running—where universal flappers often fall short due to proprietary tank peg designs unique to Mansfield systems.