I have been using this Insect killer for over 3 weeks now.  I am not sure if I expected more from it or I just have way too may mosquitoes in my backyard.  I hear the zapping noise which makes me very happy because I know it is working but I still fee some pesky mosquitoes come my way.  I keep it about 25 feet away from my sitting area and I use it along side with a Thermacell Mosquito repeller lamp which I though should give me double protection.