DoAll Lathe marked "16 ½” . This is actually a Harrison M450/500 Operation and Maintenance Manual with Parts as Exploded component Drawings.

Harrison M450 Lathe - early version, often badged "17-inch" in the USA and some other markets and with headstock control levers tipped with tapered black knobs. The end cover over the changewheels has a distinctive, large circle cast in at the top.

Harrison M450 - late version badged "450" and with headstock control levers as flat bars with rounded ends and an apron where the centre section is stepped. Usually fitted with black fascia plates on headstock face and apron: Instruction Manual, Maintenance Manual and Parts Manual as useful Exploded Assembly Diagrams with 10 electrical schematics covering the various versions.