Recently I purchased a Leicavit which to all appearances appears new or at least is in mint condition. But I have tried for fit it to my IIIG and two IIIfs and it will fit with only the most insistent effort and the lock mechanism will not travel to the full lock position. In the past I have purchased a T. Abrahamsson Rapidwinder for the screw mount cameras. and It fits better but doesn't wind the cameras (all three) very well. In the past I have talked to a few Leica camera repair men and they don't recommend using the Leicavit on the screw mount cameras. As an aside I have purchased a new Leicavit for for an MP and it works very well. Can anyone comment on this problem?