These BugsAway socks, featuring Insect ShieldŽ technology, are the perfect travel companion for wandering feet. Arch support lessens foot fatigue, and the drireleaseŽ yarn keeps feet fresh, dry, and comfortable. Permethrin, the active ingredient in Insect ShieldŽ, is invisible, odorless, and tightly bonded to the fabric fibers, and lasts the expected lifetime of the socks. It repels mosquitoes (including those carrying West Nile virus and malaria), ticks, ants, flies, chiggers and midges (no-see-ums). Insect Shield repellent lasts through 70 washings.