This is the second one I have purchased in order to extend my irrigation system and control the front garden separately from the back garden system. It's a little disengenuous to call this a computer, (hence 4 stars) - it's an automatic timer. You can control via push buttons, the time of day, the start time, the frequency of watering and the duration BUT there is no display to indicate what you have set it to if you forget. Having said that it is easy to reset. Reliability is good - I left my last timer out over the UK 2008/9 winter after a full summer of operation and it still worked when I reset it in the spring.