Replacement heavy duty reinforced stump jumper for HawkLine / Behlen Country rotary cutters, fits subcompact and medium duty 4', 5' and 6' cut mowers with 40 hp. gearboxes in both 3-point and pull type hitch. This stump jumper is 16-1/2"" diameter on the bottom and about 20-1/2" diameter at the top, has 1-1/8" bolt holes with a key slot that are 13-1/2" on center. There is a hub welded into the pan with 12 tapered splines that measures 1.57" at the top. Vertical reinforcements have been added to both side of the blade bar adding extra support and the thickness of the pan itself has been increased adding a additional 7 lbs. of steel to this stump jumper over the factory original. All HawkLine and Behlen Country mowers with 40 hp. gearboxes have a 1.57" X 12 spline shaft coming out of the bottom of the gearbox, gearboxes with a 2" x 15 spline shaft require a different stump jumper!