A LapLink cable (also known as lablink or null-printer cable) is a cable that allows one to connect two computers together to establish a direct cable connection. Horizontal menuTechnical informationTechnical informationTypeHousing: PlasticType: Cable DevicesDevicesIP Serial PortStore5 IP Relay HWg-ER02b PortBox2 IP Relay HWg-ER02a I/O Controller 2 Communication RS-232 cable LapLink (5 wire).