X-Terminator Insecticide Ear Tags contain 20% Diazinon for up to 4 months control of horn flies (including pyrethroid-resistant populations), gulf coast & spinose ear ticks & as an aid to control lice, face, stable & house flies. For use on beef & non-lactating dairy cattle. Use 2 per head. Apply with any brand of applicator. Studs coated with Infecta-Guard, Fearing's patented stud coating that helps the wound heal and keep the tag in the ear! 20 tags per package - orange.