Up for sale is forONE ONLY Diamond Stereo / flip 78 RPM Phonograph Needle Qualitone 1709XDS, (similar to Astatic N784-sd, Electro Voice EV 3380DS, 3383DS, P fanstiehl S 853-DS73,Jensen Miller T-13X, Fidelitone AC447DS ), for Tetrad A1S, A1D, C1S, C1D.