While some masks protect, there's one proven to repel. Insect Shield Equine Fly Mask from Opti-Force is made with an effective built-in insect repellent proven to repel biting flies, mosquitoes, fleas, and ticks. The Permethrin-infused Insect Shield mask provides built-in, invisible, and odorless insect protection for exposed areas around the mask, including the muzzle and ears. Comfortable Clear View Vision mesh shields your horse from insects and harmful UV rays while maintaining maximum comfort and durability. It can withstand long days in the pasture and sits away from the face and eyes to eliminate irritation for all-day wear. The tear-resistant material is highly durable and lightweight, making this equine fly mask a favorite among horse owners everywhere.