Farnam Endure Roll-On is an easy and convenient way to protect your horse’s face from flies. Its sweat-resistant formula repels house, face, horn, deer, stable, and black flies as well as gnats and can be applied around superficial wounds and abrasions. The product stays on for 5 to 7 days, and the easy-grip bottle with a large roller ball ensures effortless, even coverage for lasting protection.