Female spline is standard TE20 size 1.1/8" x 6 Spline and then converts to the modern size 1.3/8" x 6 Spline. Increases length by 4 1/8" (107mm). PTO Overrun Coupler 1.1/8" to 1.3/8". This is essential when using a cross topper/mower and also doubles as a PTO shaft size convertor.
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