The Exofficio BugsAway Sandfly Jacket, featuring Insect Shield technology, is packable bug protection. This lightweight jacket stuffs into its own security zip pocket. Reinforced shoulders hold up under straps, and the hood protects ears and face. Permethrin, the active ingredient in Insect Shield, is invisible, odorless, and so tightly bonded to the fabric fibers that it retains effective repellency through the life of the garment. It repels mosquitoes including those carrying West Nile virus and malaria, ticks, ants, flies, chiggers and midges no see ums. Insect Shield repellent lasts 70 washings.