If you want a fly spray that truly works, then use Pyranha Products. I swear by it at horse shows, and I love the aerosol spray can, because it doesn’t leave streaks and circles in the coat like regular pump sprayers. It lasts, even if they sweat a little. It does attract dust, so that is something to keep in mind with the show horses. Have a rag or soft brush to wipe over them right before the class. As always, you should test a small spot on the horse before using it on their whole body. I have known two horses to be sensitive to this product.