A modular animal ear tag with both visual identification and RFID identification components, with the visual and RFID identification components being easily mated and subsequently separated to facilitate re-use of either or both such components. Arrangement spaces are provided on both sides which interpose the lower level tray, which is in a mounting position in an apparatus body, in the width direction. Each first gear unit is driven individually by a motor and has a pair of mechanically interconnected output shafts.