Grand Tongo's light, almost-like-water formula dries quickly and leaves almost no residue, providing 12 hours of protection from mosquitoes and ticks, including those that may transmit West Nile Virus, Chikungunya, Dengue, Zika, Lyme disease, and Encephalitis. The most powerful DEET alternative, it also repels biting flies, stable flies, black flies, gnats, chiggers, sand flies, and Scottish biting midges. Active ingredient: 20% Picaridin.