The Yanmar 12915023611 main bearing set is a genuine OEM component, specifically a 0.25mm undersize set, designed for crankshaft support in various Yanmar engines. This precision-engineered bearing set is crucial for engine rebuilds where crankshaft journals have been machined, ensuring proper oil clearance and reliable engine operation. It is compatible with Yanmar 3TNV84, 3TNV84T, 3TNV88, 4TNV84, 4TNV84T, 4TNV88, 4TNV94L, and 4TNV98 engines, commonly found in agricultural and construction machinery, including compatible Case IH models.