Pre-2019 Take-A-Label dispensers where the relay was used. On the label your model number will have a suffix less than 19. So, if you have a TAL-450, the label on top will read something like TAL-450-15. You will need this photo eye. If your machine label reads TAL-250PE, 450PE, 750PE with a -18 after the model number, you will need 103P-25213.