Leica Hilfsgerat BOOWU accessory for copying documents No Reserve!

Description

This Leica accessory is designed for Leica Rangefinder type cameras.
The machine work on this accessory is simply beautiful!
Unfortunately there is no date on the packaging or paperwork.
Enclosed are three extension mounts DIN A4, DIN A5, DIN A6.
The extension mounts work like extension tubes, they extend the lens out further from the Film Plane so that the lens can focus on closer than normal objects.
DIN A4, is for copying 210 X 297 mm or 8 1/4" x 11 3/4" (Quarto)
size
paper documents.
DIN A5, is for copying 148 x 210 mm, or 5 1/4" x 8 1/4"  (Octavo) size paper documents.
DIN A6, is for copying 105 x 148mm, or  4" x 5 3/4" (Large Postcard) size paper documents.
Enclosed are four extensible rods with the numbers 4, 5, and 6 which correlate to the previously mention paper sizes.
The extensible rods have click stops so that you can feel when you have extended the rods correctly.