Found these seed plates this weekend at a roadside flea market. I dont really know what they fit to. Looks like i have a pair of corn ones for medium yellow dent with a D1344 on the back. The other set i beleive to be fert plates with a D1577 on the back. There are no other iding marks. Both plates are 6" outside and 2 3/4" on the inside. There are 3 little notches on the inside hole area and 4 drive lugs coming off the bottom.