BKM-145 multiplex coupler, secondary line end REG 6D video, light gray. Terminating coupler, secondary line multiplex for intercom according to DIN EN 50486 in 6-wire video technology. DIN rail mounting device. Last secondary line coupler to complete the secondary line cascade and supplies upstream secondary line couplers with voltage. DREHFIX function: One-man commissioning through addressing with rotary coding switch.