A press with 23 dies (both round and square) for watches of various diameters and thicknesses.

For pressing the backs onto 'difficult' watches, It avoids the embarrassment of removing a customer's watch back then not being able to push it back on;

The same machine is used for fitting on watch glasses. 

Did you spot the misprint on the label (see picture)? They mean Nylon not linen. 

SIZES

Included is the 'base' plus the following:

4 x plastic dies for square watch cases:
38mm, 32mm, 25mm, 18mm

4 x plastic dies for round watch cases:
15-25mm, 25-35mm, 35-45mm, 45-60mm

4 x flat aluminium dies:
40mm, 35mm, 28mm, 22mm

11 x deep aluminium dies:
42mm, 38mm, 36mm, 34mm, 32mm, 30mm, 28mm, 26mm, 24mm, 22mm, 18mm

INSTRUCTIONS

Find the dies that fit over the case / glass neatly and accurately, turn the wheel slowly until the glass / back clicks into place. Do it carefully, if you turn the wheel hard with the dies not in place, you will break the glass / watch. Take great care with antique watches, do not use if the back is delicately painted / enamelled.