The HII And HII-A Rockets

Just thought I'd post this diagram before I forgot. It illustrates the bits they improved and changed from the all domestic HII rocket to the new and improved HII-A rocket. Apart from a drastic reduction in parts there are some structural changes that are noteworthty. The bit that connects the first and second stage known as the interstage section was one of the places where they vastly reduced parts and mass.