Hey everyone. I now have three SW products, Model 66, Model 59 and 342-1 (NIB) I am trying to date the first two, the model 66 is SN 7K72057 and the 59 is SN A353075. They are not for sale but just trying to get a mfg date on them if possible. TIA for any information.

The model 66 is likely about 1975.

Per SCSW4, the model 59 was manufactured 1976-1977.