Permethrin 1% Synergized Pour On insecticide controls lice, face flies, and horn flies on beef cattle, lactating and non-lactating calves and dairy cattle. It eliminates keds on lambs and sheep when applied as a pour-on. This oil-based formula consists of Permethrin, synergized with Piperonyl Butoxide which guarantees a quick knockdown and adequate results. Permethrin 1% Synergized is ready to use and can be utilized as a pour on and mist spray with no dilution required, but it also has directions for use with backrubbers. One gallon will treat 25 head of 1,000 lb. cattle.