Abstract: An animal ear tag comprising two components formed of a plastics or other resilient material, a first component having a hollow stem with a flanged end which has a spike of hard plastic or other rigid material shaped from its back end with a hole for the reception of a guide pin of a reusable back plate, and the second component having a boss with a hole for fitting over such end whereby with each component detachably mounted on a jaw of a pliers like applicator and the pin of the backplate inserted through the hollow stem of the first component and into the hole of the rigid spike, on a closing of the jaws of the applicator, the spike and stem of the first component is forced through the ear of an animal, and through the hole in the second component, and on an opening of the jaws of the applicator, the rigid pin and its backplate is left within the hollow stem of the first component, and the second component retained on the hollow stem and the spike on the end of the first component, the reusable backing pla