This is a used count sensor for the old Amos mahjong machine. It's a replacement part for count sensor malfunctions, such as over-stacking or errors, in machines like Amos GABIN, Monster, Kong, and Pleasure. It has been installed in a real machine and its operation has been confirmed with AL tiles. There are 5 in stock. Operation has not been confirmed with transparent ALC tiles or Martel tiles. If you are using the above tiles, please consider the photo sensor replacement board that is listed separately. Please comment with the number of pieces you need before purchasing.