This is an essential item if you are restoring, riding or racing your now vintage DT250. This is a new in the package ring set for the 1977 DT250D, 1978 DT250E This is a 2 pc piston rings set..everything to get your piston compression back where it should be. Correct replacement for long discontinued Yamaha # 1M1-11610-00-00. This is the Standard size (STD.) 70mm ring set. Get your old bike up and running again. We only sell the best! This is a top-quality aftermarket item. Good stuff if you are riding or restoring or AHRMA racing these cool bikes. We also stock the helpful engine Gasket Set and engine crankcase Oil Seal Kit for these bikes too on our website if you may need also.