This is a new in the package standard size (STD) Piston Ring Set  (this is a complete ring set for All 4 Pistons!) for the  1976 1977 1978 1979 1980 1981 1982 1983 Kawasaki KZ650 Z650 motorcycle.   This is a standard size (STD) ring set.  This has the 2 compression rings and the lower 3pc oil control rings for all 4 pistons, everything to get your pistons/ engine running nicely again.   We only sell the best! This is a top-quality aftermarket item shipped new in the package.  Correct for part # 13008-059.  Good stuff if you are riding or restoring or AHRMA racing one of these cool bikes. We also stock the helpful complete engine gasket set, oil seal kit and carb kits if you may need also.  That is it!