This agitator ring is the rotating component inside the fertilizer spreader hopper that prevents bridging and ensures a steady material flow to the metering mechanism. It sits at the base of the hopper, rotating against the inner wall to break up clumps and keep the fertilizer moving toward the outlet. A worn or missing ring allows material to pack around the agitator shaft, leading to inconsistent feed rates and uneven application. As an original part from the manufacturer, its outer and inner diameters match the hopper floor and agitator shaft geometry, so no shimming or adapter is needed during replacement.