Standard Replacement John Deere Mower Blade for John Deere Models Equipped with 42-inch Mowing Deck Center Hole: 7-point star center hole Item: 490-110-0134 O.E. Replacement Part Number: GX20249 , GY20567 , 491-139 , 91-139 , 191-139 , 330-615 , 10635 Features 7-point star center hole Replaces O.E. # GX22151 Fits John Deere lawn and garden tractors with a 42" cutting width Contains one blade, two are required