The BugsAway Lumen Tee, featuring Insect Shield¨ technology, is ideal for hot days when you need to stay cool and protected at the same time. 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. Do not dry clean.