It will Fit the Following Thorens Turntables: Thorens TD 121, Thorens TD 124, Thorens TD 124 MKII, Thorens TD 135, Thorens TD 184, Thorens TD 224. As you Move the Magnet Closer to the Step Pulley the Turntable Platter Speed will Slow a Little, Move the Magnet Further away & it will Speed Up a Little.
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