This white paper will give a short overview over the contact system and common surface coatings used for electronic connectors. Furthermore, the focus is on a comparison between hard gold and hard gold flashed palladium-nickel because, in the field of data transmission via electronic connectors, these two coatings are the most common options used. Although this topic has been discussed earlier, there are still many questions. The respective characteristics and advantages of these two surfaces will be considered in more detail and confirmed by investigations done in the HARTING Quality and Technology Center.