Light Shield is extremely effective at creating a mosquito barrier and protect people and animals in the illuminated area from pesky mosquitos.   The disadvantages of the product are that you have to stay within the illuminated area, the product is only effective at in the evening and at night and the light that the divice gives off is very yellow.  Some advantages of the device are that it is as easy to install as screwing in a light bulb, turns on with the flick of a light switch, chemical free, and has a very low operating cost. Light Shield has the cheapest operating cost when measured in terms of cost / hour of mosquito coverage / square ft with the exception of mosquito netting.