510 Spring Tempered Phosphor Bronze is an alloy of copper that exhibits excellent strength, formability, and durability. Alloy C51000, Grade A Phosphor Bronze, H08 (spring) has a high resistance to fatigue and corrosion making it ideal for electronic connectors and spring contacts. Phosphor Bronze has excellent cold working and electrical properties as well as high formability with the added benefit of welding, brazing and soldering capabilities.