Legrand AlphaRex³ D21, digital weekly timer, 1 channel, 56 switching programs, operating voltage 24 V 50/60 Hz and DC, 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.