Fits many 42" cut Poulan, Husqvarna and Craftsman mowers. This blade set replaces OEM#s 127843, 138498, 138971, 138971X431, 53-21278-43, 53-21384-98 and 53-21389-7. 2 Blades are required for 42"cut deck. This blade measures 21" long by 2 1/4" wide with a 5 point star center hole.