The ekey net control unit for series installation with four relays can control four devices with its four relays. This control unit is used to open building doors, company doors, garage doors, etc. The control unit is intended for use in the home and business sector. The ekey net control unit REG 4 is intended for fixed installation on a DIN rail in e.g. a distribution box and for use in protected indoor areas. This control unit has LEDs for signaling but no display. To operate it, you also need a suitable finger scanner, an ekey net converter LAN, a suitable power supply and the complete ekey net software.