This is a DC powered timer - not AC so it must have a quartz clock inside (cheap AC timers just use AC pulses to track time). It keeps track of the day of the week as well as the time (down to the second!) so you can have your electric blinds roll up on weekdays and not do anything on Saturday and Sunday. It will control AC devices (spliced into an extension cord to run a lamp without voiding warranty) but you still need to run the clock on DC power. As such the clock has a rechargable battery to keep time without power.
It does allow you to program 8 "events" (on & off) but for one device only (great for day of week timing). You will have to buy 2 if you want to turn on a radio and roll up a blind (at different times) for instance. It has a reverse connection for turning something off when something else goes on (only time 2 devices are connected).
About the only thing I could suggest for product improvement is the addition of another relay (or 2) to control 2 devices (or more) with one clock module since clock modules seem (to me) to be the expensive part of this product (clock chip, memory, backup battery, display, buttons). Perhaps a "Double Time" product or modular plug in (jack connect 3 relay cubes to main timer) so this product can become more useful for all timing needs. I won't have to set the time for all 3 of these.
Put me down for another...