The Permethrin ""No Mite Strip"" is the most effective, efficient, and economical application of an insecticide to protect your flocks from Northern Fowl Mites. As the birds touch the strip, the insecticide transfers directly from the surface of the strip to the birds. None of the insecticide contaminates the environment and you can achieve up to two years of continuous protection with these strips. - Usage: 1 Strip per 5 birds.