For horse spray I use Endure and for fly control I use Spalding fly control. Have been using both products for years and am very happy with the two products. We are surrounded by cattle ranches and might find one or two flies in the house all year. As for horse flies haven't found how to eliminate them yet but the Endure keeps them off. Don't know how wise it is but I mist myself with the Endure when riding. Does a better job I think on repelling all bugs of all kinds.