This insect trap is engineered for 3-way protection. First, a UV fluorescent bulb generates a warm light, attracting insects. Then a second lure, an exclusive Ti02 titanium dioxide-coated surface, produces CO2 (the same gas we emit when we exhale) that's irresistible to mosquitoes. Third, a powerful, yet whisper-quiet vacuum fan sucks insects into the retaining cage where they dehydrate and die. A unique twist-to-close feature ensures that any insects still alive in the retaining cage will not escape when the trap is turned off. Convenient for travel, RV's, patios and pantries, the DYNATRAP ultralight can be placed just about anywhere (use outdoors only in a covered, protected area, for example, a garage, screened-in porch or four-seasons room).