This inner blade is the rotating cutting element inside the seed-metering mechanism of a grain seeder. It shears through the seed column to regulate the flow of grain from the metering cup into the delivery tube. The blade mounts on the metering shaft and rotates in close proximity to the stationary housing; wear on its cutting edge increases the gap, allowing seed to pass unevenly and causing skips or overplanting in the row. As an original component from the implement manufacturer, the blade profile and edge geometry match the housing’s internal contours, so the metering rate remains within the calibration range without re-shimming or adjustment.