Endure® Gold Gold Killer Fly & Mosquito Control protects horses from house flies, stable flies, face flies, horn flies, gnats and mosquitoes. It also kills ticks and deer ticks that may transmit Lyme disease. Offers a solution with two new-to-horses active ingredients: Acetamiprid and Etofenprox are a killer combination for equine fly control. Horse owners can keep them working well by establishing an effective fly control program that combats resistance. Spraying flies with the same product all season puts immense selection pressure on flies and speeds development of resistance. Responsible fly control means establishing an effective fly control program with a basket of products that block, repel and reduce the fly population. The only equine fly spray with Acetamiprid and Etofenprox.