This is a new in the package Piston Rings set (2 set of rings so  enough to complete 1 engine) that fits all 1977 1978 1979 GS450 models.This is a standard size (STD) ring set which is correct replacement for  65mm Standard bore pistons. Correct replacement for #12140-45013.    Each of the sets has the 2 compression rings and the lower 3pc oil control rings for the pistons, everything to get your pistons/ engine running nicely again.  Very helpful and hard  to find item!  Get your old bike up and running again. We only sell the best! This is a top-quality aftermarket item shipped new in the package.    Good stuff if you are riding or restoring or  racing these cool bikes.

This is for all 1977-1979 models B, C, N, E