They will not fit 247 model craftsman they use 6 point star hole . 2 blades required for 42" cut decks. AYP/Roper/Sears: LTH1342, LTH1342A, YTH1542XP, YTH1542XPG, 2 for 42", 2 for 42", 20" Cuts. Center Hole: 5 Point Star.
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