Tin-Plated Brass Pins and Sleeves—Tin-plated connectors are best for unexposed, mated connections, since they may corrode in harsh environments. Use them in applications where they won’t have to be mated and unmated multiple times. They’re more prone to noise on a signal line than gold-plated connectors, so they should be used in areas that create low noise in contacts.

Gold-Plated Brass Pins and Sleeves—Gold-plated connectors are more corrosion resistant than tin-plated connectors, making them best for exposed, unmated connections in harsh environments. They’re also more wear resistant, so they can be mated and unmated for more cycles. Good for low-voltage analog circuits, they stand up to noise on signal lines better than tin-plated connectors.