Transgenic crops producing Bacillus thuringiensis (Bt) toxins kill some key insect pests. but evolution of resistance by pests can reduce their efficacy. The predominant strategy for delaying pest resistance to Bt crops requires refuges of non-Bt host plants to promote survival of susceptible pests. To delay pest resistance to transgenic cotton producing Bt toxin Cry1Ac. https://allfixelectricales.shop/product-category/plastic-door-film/