Say bye-bye to pesky pests with the Farnam Repel-X pe Concentrated Fly Spray for Horses. This concentrated fly spray is ideal when you need large amounts of spray to protect your horses without going over budget. This do-it-yourself concentrate is easy to use. Just add water and every pint of concentrate creates a gallon of ready-to-use fly spray. This water-based spray helps to repel and kill horn flies, house flies, stable flies, horse and deerflies, gnats and mosquitoes. It’s also effective against ticks, including deer ticks that may transmit Lyme disease.