1-inch FIP (Female Iron Pipe) x Press Dielectric Union. Specifically designed to prevent galvanic corrosion (electrolysis) when joining dissimilar metals, such as copper and galvanized steel. Fully compliant with NSF/ANSI 61 & 372 standards, ensuring this union is safe and legal for all potable water applications, including high-temperature residential and commercial heating systems up to 180 degrees Fahrenheit.