Count on Ready-Aire heater cores to fit right, install easily and provide long, dependable service life. Manufactured in our ISO-certified North American plants, they're constructed of premium OE-approved materials. Advanced, high-strength alloys reduce premature failure, even in harsh, corrosive environments. The core tube has an air-side braze liner which is the first layer of defense against corrosion. If corrosion should reach the core layer, a band region of special alloy elements will force the corrosion to spread uniformly over the entire surface, rather than allowing the corrosion to continue down through the material thickness, causing pitting. An extra water-side layer is made up of a high-percentage zinc alloy which also acts as a barrier, providing enhanced corrosion protection and longer product life.