Balancer comparison - Cast vs Forged crank

Was cleaning out my garage in Hawaii when I came across these balancers. Thought I'd take side by side pics of them before I threw them out. The one on the left is for a cast crank 340, I know for sure because it says "use with 340 cast crank only" cast right into it :D The one on the right is out of my early 72 340 that came with a forged crank.