Legrand AlphaRex³ D21 astro, astro timer with combination function, 1 channel, 56 switching programs, operating voltage 230 V 50/60 Hz, astro function (sunsets/sunrises) can be combined with weekly timer function. Control directly from the distribution board, no separate light catcher required. 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, control input, 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.