This is a writing board for blind people with 2 pens.
Here the dots are pressed through the blade with the stylus mirror-inverted.
Below is a six-point shape that prevents mam holes from pressing into the paper.
When the sheet is inserted, the recesses of the lower plate cannot be felt and cannot be seen because the paper is in between.
Rectangular recesses are punched into the upper part of the writing board, which almost form the grid for the individual characters - similar to a chequered exercise book. The dot combination of a Braille sign can now be pierced into each recess.