Mortein All Insect Killer is odourless and it can kill insects such as mosquitoes, flies, cockroaches and ants instantly on direct spray and up to 2 times faster. Close all doors and windows. Switch on the lights before spraying. Spray upwards throughout the room for about 3-4 seconds for a medium size room of 60m3. Leave the room after spraying and keep the door and windows closed for at least 10 minutes before re-entry. Ensure the room is properly ventilated upon entering.