OFF! Mosquito Lamp Refills are sold separately for use with OFF! Mosquito Lamp I. Each refill contains two candles and two repellent diffusers. The OFF! Mosquito Lamp I provides long-lasting protection for any outdoor party, by repelling annoying mosquitoes in an area up to 10 ft. x 10 ft. Simply activate the diffuser by lighting the candle and you can be sure your get-together won’t have any unwanted guests for up to 6 hours. The heat from the candle activates repellant from the Diffuser, releasing mosquito protection. Get Back out There