Y-Tex Livestock Insecticide Python Dust ShakerPYthon II Dust is the only dust to contain two novel active ingredients for maximum efficacy against all major livestock ectoparasites. Zetacypermethrin is a 5th generation pyrethroid with enriched S isomer content that is highly active against horn flies, face flies, ticks and other pests. Used for lactating and non lactating dairy cattle, beef cattle, sheep, goats & horses Helps overcome metabolic resistance in insects and and synergizes the