This roll-on repellent is formulated with water instead of oil, giving it a lighter feel that resists sweat and rinses away without leaving behind a greasy film. Three active ingredients, permethrin, pyrethrins, and piperonyl butoxide, work together to knock down and repel flies, fleas, ticks, gnats, and mosquitoes on contact. The bottle uses a smooth rollerball tip rather than a sprayer, which makes it easier to treat a horse's face, ears, and other sensitive spots without the noise or overspray of a pump bottle. A light citronella scent is built into the formula. The product comes ready to use directly from the 3 oz bottle with no mixing or dilution required. As with any topical insecticide, label directions should be followed and contact with eyes should be avoided.