Pre-Strike® Mosquito Torpedo® larvicide is an easy and effective way to stop mosquitoes before they become breeding, biting adults. Just drop Mosquito Torpedo® larvicide into standing water where it slowly and continuously releases an insect growth regulator (IGR) that prevents adult mosquito development for up to two months. Each torpedo provides up to 60 days of protection. Mosquito Torpedo® larvicide also leaves water crystal clear with no unsightly debris. Available in 5 pack containers, Mosquito Torpedo® larvicide won't harm humans, animals, fish or vegetation when used as directed. It's great for use in bird baths, animal watering troughs, containerized water gardens, privately-owned ponds, unused swimming pools or spas, flooded areas, roof gutters and tree holes, rain barrels, ornamental fountains and any place you have standing water.