All of the Amphenol RF SMA contacts have a gold finish. The electrical performance of gold is excellent. Whenever corrosion resistance, an untarnished surface, and a constant and low contact resistance are required, gold is the most suitable plating material. Various metals can be used for the center conductor in an RF connector. Brass is the most popular contact material, as it conducts thermal heat and electricity well. Phosphor bronze is an alloy of copper, tin, and phosphorus. The tin increases the corrosion resistance and strength of the alloy. Beryllium copper has good corrosion resistance and can be exposed to high temperatures without risking melting and deterioration. This is a combination of brass and copper and used in some right angle connector applications.