Wow.  Thank you, thank you.  I use this outdoor in my Mexico home and it works great.  I love hearing the zapping noise and knowing there is one less mosquitos to bite me.  I purchased the 1/2 acre and I only have a small yard.  Get whichever size you can afford.  Your neighbors will love you.  I keep this on from dusk to dawn and I love the fact that the insects just fall to the ground.  No trays to empty.