The Grundfos 519602 1" Iron Pump Flange Pair provides a robust flanged connection solution for 1" circulator pumps in hydronic heating and hot water systems. These cast iron flanges mount to the pump housing and piping to deliver a secure and reliable joint for system circulation. The set is designed to work with Grundfos circulator models that require a 1" flanged connection, allowing for straightforward installation and leak-resistant performance.