As most of you are probably aware, the Master sled doesn't have the most rigid topstage in the world. I have this handy clamp that CP made to completely lock down the dovetail to the stage. I can find no literature about this thing anywhere on the internet, except in one interview with GB when he was working on Bulworth. Today I talked to Lyn Taylor and he immediately recognized it and confirmed that Tiffen doesn't make it. I would love to get my hands on another one to have as a backup, but that may prove to be more trouble than it's worth. Out of curiosity, I was wondering if any current or former Master owners used this part or know any history attached to it.