Bought this new last year, still in the wrapper. Never used. Pacific part no. PDAC 211. Works for PDP600 series pedals. These have a 6 mm square shaft. The PDP500's and earlier versions have a round shaft with a straight cut on one side. It will not fit those. Basically fits any PDP, DW, or other mfg pedal with a 6 mm square shaft. These cost from $53-$65 new depending on source....asking $30 plus shipping.