Precious metal coatings (such as gold, palladium and their alloys) are inert and have no coating. Therefore, for these surface treatments, metal contact is “automatic”. What we must consider is how to keep the “nobility” of the terminal surface from external factors such as contamination, substrate diffusion, and terminal corrosion. Non-metallic coatings, especially tin and lead and their alloys, cover an oxide film, but when inserted, the oxide film can easily crack and establish metal contact areas. Mokolink electronic connectors are only plated with thick gold and not with thin gold. Plated with precious metal terminals. Precious metal terminal plating refers to the precious metal covering the bottom surface, usually nickel. Plating thickness of ordinary connector: 15 ~ 50u gold, nickel 50 ~ 100u. The most commonly used precious metal coatings are gold, palladium and other alloys. Gold has excellent electrical and thermal conductivity, and is resistant to corrosion in any environment. It is the most ideal plating material. In connectors requiring high reliability, the main plating is gold. But because of the high price of gold, people have been looking for alternative materials. Palladium is also a precious metal. Compared with gold, palladium has higher resistance, lower heat transfer, and poor corrosion resistance, but it has the advantages of high friction resistance. Usually, palladium-nickel alloy (80 ~ 20) is used in the connector post (POST).