TOS SN-40, SN-45, SN-50, SN-40B, SN-45B and SN-50B Lathes: Operator's Instruction and Maintenance Manual and a separate Parts Manual as clear sectional drawings together with an electrical schematic and a reproduction of the screwcutting charts. The two manuals were originally published separately, but both are required as the Operation and Maintenance Manual continually refers to Part Numbers that are only in the Parts Manual. The Parts manual also has references to other TOS lathes that used the same parts, including the SN70, SN71, SN55, SN30, SN55, etc.