XT90 connectors have a high-temp Nylon casing that houses the gold plated spring connectors which get placed into the injection mold during the manufacturing process. Since the housing is molded around the connectors it ensures that the connectors always stay aligned so that you can quickly and easily plug in and unplug. The XT90 connectors provide a solid, high-amp connection - perfect for applications up to and beyond 90 amps!