The invention is directed to an improved RFID system. The system provides
a transponder that can communicate over at least two different
frequencies so that the real time performance of the transponder can be
improved without losing backwards compatibility. The system provides an
improved apparatus and method that allows the end user to customize and
program identification tags. The system also provides an ear tag, which
may be in button form, for use on livestock with superior durability and
overall performance in the field.