ENGUARD is a brand new and effective insect repellent that is totally safe for all the family. ENGUARD is activated simply by rubbing or scrunching. Once activated ENGUARD lasts 3 hours at 90% effectiveness, just rub or scrunch again to re-activate. ENGUARD works by continually releasing a fresh smelling natural vapour, which is safe for even the most sensitive skin. During normal use, ENGUARD remains active, creating a comforting, long-lasting, protective ”Bite Free Zone” around you of up to 50 cm (20″) from the surface of the fabric.