Cutter Backwoods Insect Repellent is ideal for prolonged outdoor activities, with a formula that repels insects up to 10 hours. The sweat-resistant aerosol spray formula provides long-lasting protection against mosquitoes and other biting insects. This 25 percent DEET formula repels mosquitoes, including those that may transmit the Zika, West Nile, Dengue and Chikungunya viruses. Cutter Backwoods Insect Repellent wards off other annoying insects, too, including ticks, biting flies, gnats, no-see-ums, chiggers and fleas.