I ordered a L0 size backplate recently and received an L00 (they are easily confused). The supplier immediately sent me the correct item and, although I was quite prepared to return the one sent in error, the dealer has very generously told me to keep it. So, if nobody in the club to which I belong wants it, as I am giving any member the first chance to acquire it, it will be advertised at about half-price for anyone else who may have a use for it. I understand the L00 fitting is found on Harrison 140, L5, L5A & L6 lathes and very possibly the Boxford VSL (?).