Simon Kohler used to sell them before he went to hornby. i still use the duettes but i'm afraid i cant answer your question.
I think the best thing to do with these is if they are working, leave them alone and use them as they are. there are reasons why these are banned now.
Peter
I think the best thing to do with these is if they are working, leave them alone and use them as they are. there are reasons why these are banned now.
Peter