The McCormick 1822581M1 is a genuine standard piston ring designed for a bore diameter of 91.44 mm. This essential engine component ensures proper compression and oil control in a wide range of agricultural machinery, including numerous Massey Ferguson, Landini, and McCormick tractor models, as well as various Perkins engines such as the AD3.152, A4.236, and 1104 series. It is a critical part for engine overhaul and maintenance, ensuring optimal performance and longevity.