The most common plug used with twisted pair network cables is Registered Jack 45 (RJ45). It is a standardized connector used with Ethernet cables and is designed to connect networking devices such as computers, switches, and routers. RJ45 connectors have eight pins and are usually used with Category 5 (CAT5) or higher-rated cables, which are commonly used in local area networks (LANs) and wide area networks (WANs).