This is the original HD trans sprocket spacer next to the new Baker spacer.
From Baker's web site
sprocket spacer
If you are a seasoned technician, you have seen a severely worn sprocket spacer. Over time and miles with dirt and grit, the stock 33344-94 spacer is too soft and it gets gouged by the seal that rides against it. As the spacer gets gouged, the seal relaxes. When the seal relaxes, the leaks begin. Our sprocket spacer is a direct replacement for the stock spacer except ours is case hardened steel that has a Rockwell ‘C’ hardness of 55. No more gouging, no more leaks.
Sprocket Spacer, 94-Up Big Twin & Sportster p/n 33344-94S
Whether you agree with the hype or not, the Baker part is cheaper then the HD part. And the the recess is cut into both sides, so it can be installed in either direction.