I have no idea. I have done some googling on this subject but haven't turned up anything yet. Seems I do recall seeing photos showing the early NG grips to be a good bit longer than what they sell today but I can't find anything about the specs of the older clubs. Maybe if Todd or Tim sees this they will know. NG has gone through some changes over the years, both in teaching and equipment so I probably spoke out of turn on the subject of the longer irons. I was making my statement based on the only ones I have ever seen (G2's I think and the newer Pipelines which I have)and the Pipelines are only about an inch longer. I may be wrong about the length of the Original Cavity Backs but I have a friend who has a set of these and I can check with him to see how much longer they are. The only "Hammer" I've ever heard of is the driver NG sells. But JK, Right Way Gold and NG go back several years before I became aware of NG.