The McCormick 81669C1 is a genuine OEM piston ring designed for various McCormick agricultural tractor models, including B275, B414, 354, 374, 384, 434, and 444. This essential engine component features a bore diameter of 79.375 mm and ensures optimal cylinder sealing for efficient engine compression and performance. Manufactured to original equipment specifications, it provides reliable operation and durability for engine maintenance and rebuilds.