Legrand AlphaLux³ D21, twilight switch with digital weekly timer, including light catcher 412860, 1 channel, operating voltage 230 V 50/60 Hz, setting range 1 - 100,000 lux, switch-on and switch-off delay 30 ... 300 sec. (adjustable), 56 switching programs, program creation directly on the device or with PC, AlphaSoft, PC adapter (412873) and data key (412872). Permanent ON/OFF, holiday program, random program, 1 hour test, PIN code lock, operating hours counter, background lighting, automatic summer/winter time changeover, 5 year power reserve, accuracy +/- 0.1 sec/day, shortest switching time: 1 sec., zero-crossing switching. Switching output: 1 changeover contact.