Updated 12/4/2015:  this was my second one.  The first lasted almost two years. This one just went out after 4 months.  I'm going to try to guy a new bulb (only because it's cheaper than the entire unit) to see if this works.  I sure hope so.  Purchase in August:  I moved into a new home and the mosquitoes were a nightmare.  This insect killer works better than I had even hoped for.  My sister is so convinced that she is buying one for her home as well.