The natural pyrethroids act as a bite inhibitor, discouraging actual biting. Each application of Expedition 100+ will last for over 10 hours. Re-application may be required in areas with high temperature & humidity. Use sufficient repellent to cover exposed areas of skin To put on face & neck, dispense a small amount on the palm of your hand & rub on If using in conjunction with sun cream, apply the cream first & allow this to absorb into the skin & then apply the insect repellent Re-apply repellent more often in areas of high humidity or when you perspire a great deal Re-apply after swimming or showering Do not use DEET on any open wounds or rashes Keep DEET out of your eyes, mouth, ears & avoid inhaling it