Kills on contact! Faster killing Raid Ant Killer 16 kills ants in two ways: 1) It kills bugs fast - on contact and 2) It keeps on killing with residual action even after you spray, for up to 4 weeks. Contact kill gives you immediate results when spraying individual ants. Residual kill keeps on killing the ants that return to the areas you have sprayed. Contains no CFCs or other ozone depleting substances. Federal regulations prohibit CFC propellant in aerosols. For household use only.