http://tinyurl.com/ltse7jqSet Of 3, Gator 3-in-1 Mulching Blades to Replace John Deere Blades GY20852, GX21784, GX21785Product Review Click on the link for more reviewsPrice is for a set of 3 Geniune Gator 3-In-1 blades48" John Deere, replaces GX21784, GX21785, or GY20852 (3pk)Hardened steel for extended blade life. All Oregon blades are austemper heat treated17" Long, 2.50" Wide, .187" ThickMounting hole is a 7 point star hole