Kuchar combine parts have threshing elements and we ran them for a while and then switched over to his complete rotor. But the elements are quite a bit heavier, at least twice the weight of Deere elements, so the rotor has more inertia. They aren't smooth like the factory 50 series elements. Because of the rasp bar bolted on the element it helps move the crop through the combine better and when the bar gets worn or broken it's cheaper to replace than the factory elements. www.combinehighperformanceparts.com/home.php?p=sts_raspbar